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Antibiotic

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Testing the susceptibility of Staphylococcus aureus to antibiotics by the Kirby-Bauer disk diffusion method. Antibiotics diffuse out from antibiotic-containing disks and inhibit growth of S. aureus resulting in a zone of inhibition.

In common usage, an antibiotic is a substance or compound (also called chemotherapeutic agent) that kills or inhibits the growth of bacteria. ^[1] Antibiotics belong to the group of antimicrobial compounds, i.e., those for treating infections caused by microorganisms, including viruses, fungi, and protozoa.

The term "antibiotic" (from the Ancient Greek: ἀντί – anti, "against" and Ancient Greek: βίος – bios, "life") was coined by Selman Waksman in 1942 to describe any substance produced by a micro-organism that is antagonistic to the growth of other micro-organisms in high dilution. This original definition excluded naturally occurring substances, such as gastric juice and hydrogen peroxide (they kill bacteria but are not produced by micro-organisms), and also excluded synthetic compounds such as the sulfonamides (which are antimicrobial agents). Many antibiotics are relatively small molecules with a molecular weight less than 2000 Da.^{[citations needed]}

With advances in medicinal chemistry, most antibiotics are now modified chemically from original compounds found in nature, as is the case with beta-lactams (which include the penicillins, produced by fungi in the genus Penicillium, the cephalosporins, and the carbapenems). Some antibiotics are still produced and isolated from living organisms, such as the aminoglycosides; in addition, many more have been created through purely synthetic means, such as the quinolones.^{[citations needed]}

[hide]

[edit] History of antibiotics

See also: Timeline of antibiotics

Penicillin

Although potent antibiotic compounds for treatment of human diseases caused by bacteria (such as tuberculosis, bubonic plague, or leprosy) were not isolated and identified until the twentieth century, the first known use of antibiotics was by the ancient Chinese over 2,500 years ago.^[2] Many other ancient cultures, including the ancient Egyptians, ancient Greeks and medieval Arabs already used molds and plants to treat infections, owing to the production of antibiotic substances by these organisms, a phenomenon known as antibiosis^[3]

Quinine became widely used as a therapeutic agent in the 17th century for the treatment of malaria, the disease caused by Plasmodium falciparum, a protozoan parasite.

Antibiosis was first described in 1877 in bacteria when Louis Pasteur and Robert Koch observed that an airborne bacillus could inhibit the growth of Bacillus anthracis.^[4] The antibiotic properties of Penicillium sp. were first described in England by John Tyndall in 1875.^[5] However, his work went by without much notice from the scientific community until Alexander Fleming's discovery of Penicillin.

Modern research on antibiotic therapy began in Germany with the development of the narrow-spectrum antibiotic Salvarsan by Paul Ehrlich in 1909, for the first time allowing an efficient treatment of the then-widespread problem of Syphilis. The drug, which was also effective against other spirochaetal infections, is no longer in use in modern medicine.

Antibiotics were further developed in Britain following the discovery of Penicillin in 1928 by Alexander Fleming. More than ten years later, Ernst Chain and Howard Florey became interested in his work, and came up with the purified form of penicillin. The three shared the 1945 Nobel Prize in Medicine. In 1939, Rene Dubos isolated gramicidin, one of the first commercially manufactured antibiotics in use during World War II to prove highly effective in treating wounds and ulcers.^[6] Florey credited Dubos for reviving his research on penicillin.^[6]

Prontosil, the first commercially available antibacterial antibiotic was developed by a research team led by Gerhard Domagk (who received the 1939 Nobel Prize for Medicine for his efforts) at the Bayer Laboratories of the IG Farben conglomerate in Germany. Prontosil had a relatively broad effect against Gram-positive cocci but not against enterobacteria. The discovery and development of this first sulfonamide drug opened the era of antibiotics.

[edit] Antimicrobial pharmacodynamics

Main article: Antimicrobial pharmacodynamics

Points of attack on bacteria by antibiotics

The environment of individual antibiotics varies with the location of the infection, the ability of the antibiotic to reach the infection site, and the ability of the microbe to inactivate or excrete the antibiotic. At the highest level, antibiotics can be classified as either bactericidal or bacteriostatic. Bactericidals kill bacteria directly where bacteriostatics prevent cell division. However, these classifications are based on laboratory behavior; in practice, both of these are capable of ending a bacterial infection.^[7] The bactericidal activity of antibiotics may be growth phase dependent and in most but not all cases action of many bactericidal antibiotics requires ongoing cell activity and cell division for the drugs' killing activity.^[8] The minimum inhibitory concentration and minimum bactericidal concentration are used to measure in vitro activity antimicrobial and is an excellent indicator of antimicrobial potency. However, in clinical practice these measurements alone are insufficient to predict clinical outcome. By combining the pharmacokinetic profile of antibiotic with the antimicrobial activity several pharmacological parameters appear to be significant markers of drug efficacy.^[9]^[10] The activity of antibiotics may be concentration-dependent and characteristic antimicrobial activity increases with the progressively higher antibiotic concentrations.^[11] They may also be time-dependent where the antimicrobial activity does not increase with increasing antibiotic concentrations, however it is critical that the minimum inhibitory serum concentrations is maintained for a certain length of time.^[11]

[edit] Administration

Oral antibiotics are simply ingested, while intravenous antibiotics are used in more serious cases, such as deep-seated systemic infections. Antibiotics may also sometimes be administered topically, as with eye drops or ointments.

[edit] Antibiotic classes

Main article: List of antibiotics

Unlike many previous treatments for infections, which often consisted of administering chemical compounds such as strychnine and arsenic, with high toxicity also against mammals, most antibiotics from microbes have fewer side-effects, and high effective target activity. Anti-bacterial antibiotics can be categorized based on their target specificity: "narrow-spectrum" antibiotics target particular types of bacteria, such as Gram-negative or Gram-positive bacteria, while broad-spectrum antibiotics affect a wide range of bacteria. Antibiotics target bacterial cell wall, penicillins, cephalosporins or cell membrane, polymixins, or interfere with essential bacterial enzymes quinolones, sulfonamides usually are bactericidal in nature. Whilst those which target protein synthesis such as the aminoglycosides, macrolides and tetracyclines are usually bacteriostatic.^[12] In the last few years three new classes of antibiotics have been brought into clinical use. This follows a 40-year hiatus in discovering new classes of antibiotic compounds. These new antibiotics are of the following three classes: cyclic lipopeptides (daptomycin), glycylcyclines (tigecycline), and oxazolidinones (linezolid). Tigecycline is a broad-spectrum antibiotic, while the two others are used for Gram-positive infections. These developments show promise as a means to counteract the growing bacterial resistance to existing antibiotics.

[edit] Production

Main article: Production of antibiotics

Since the first pioneering efforts of Florey and Chain in 1939, the importance of antibiotics to medicine has led to much research into discovering and producing them. The process of production usually involves screening of wide ranges of microorganisms, testing and modification. Production is carried out using fermentation, usually in strongly aerobic form.

[edit] Side effects

Side effects are many, varied and can be very serious depending on the antibiotics used and the microbial organisms targeted. Adverse effects can range from fever and nausea to major allergic reactions including photodermatitis.^{[citation needed]} One of the more common side effects is diarrhoea, sometimes caused by the anaerobic bacterium Clostridium difficile, which results from the antibiotic disrupting the normal balance of the intestinal flora,^[13] Such overgrowth of pathogenic bacteria may be alleviated by ingesting probiotics during a course of antibiotics.^{[citation needed]}. An antibiotic-induced disruption of the population of the bacteria normally present as constituents of the normal vaginal flora may also occur, and may lead to overgrowth of yeast species of the genus Candida in the vulvo-vaginal area. ^[14] Other side effects can result from interaction with other drugs, such as elevated risk of tendon damage from administration of a quinolone antibiotic with a systemic corticosteroid.

[edit] Drug-Drug interactions

[edit] Contraceptive pill

Hypothetically, interference of some antibiotics with the efficiency of birth control pills is thought to occurs in two ways. Modification of the intestinal gut flora resulting in the reduced absorption of the estrogens and induction of hepatic liver enzymes which metabolise the pills active ingredients faster may affect the pill's usefulness.^[15] However, there have been no conclusive studies that proved that disruption of the gut flora affects contraception; on the contrary, the majority of the studies indicate that antibiotics do not interfere with contraception.^[15]^[16], even though there is a possibility that a small percentage of women may experience decreased effectiveness of birth control pills while taking an antibiotic.^[17] Interaction with the combined oral contraceptive pill through induction of hepatic enzymes by the antifungal medication griseofulvin and the broad-spectrum antibiotic rifampicin has been shown to occur. It is recommended that extra contraceptive measures are applied during antimicrobial therapy using these antimicrobials.^[15]

[edit] Alcohol

Alcohol can interfere with the activity or metabolization of antibiotics. ^[18] It may affect the activity of liver enzymes, which break down the antibiotics.^[19] Moreover, certain antibiotics, including metronidazole, tinidazole, co-trimoxazole, cephamandole, ketoconazole, latamoxef, cefoperazone, cefmenoxime, and furazolidone, chemically react with alcohol, leading to serious side effects, which include severe vomiting, nausea, and shortness of breath. Alcohol consumption while taking such antibiotics is therefore explicitly prohibited.^[20] Additionally, serum levels of doxycycline and erythromycin succinate may, in certain circumstances, be significantly reduced by alcohol consumption. ^[21]

[edit] Antibiotic resistance

Main article: Antibiotic resistance

SEM depicting methicillin-resistant Staphylococcus aureus bacteria.

The emergence of antibiotic resistance is an evolutionary process that is based on selection for organisms that have enhanced ability to survive doses of antibiotics that would previously been lethal.^[22] Antibiotics like Penicillin and Erythromycin which used to be one-time miracle cures are now less effective because bacteria have become more resistant.^[23] Antibiotics themselves act as a selective pressure which allows the growth of resistant bacteria within a population and inhibits susceptible bacteria.^[24] Antibiotic selection of pre-existing antibiotic resistant mutants within bacterial populations was demonstrated in 1943 by the Luria-Delbrück experiment.^[25] Survival of bacteria often results from an inheritable resistance.^[26] Any antibiotic resistance may impose a biological cost and the spread of antibiotic resistant bacteria may be hampered by the reduced fitness associated with the resistance which proves disadvantageous for survival of the bacteria when antibiotic is not present. Additional mutations, however, may compensate for this fitness cost and aids the survival of these bacteria.^[27]

The underlying molecular mechanisms leading to antibiotic resistance can vary. Intrinsic resistance may naturally occur as a result of the bacteria's genetic makeup.^[28] The bacterial chromosome may fail to encode a protein which the antibiotic targets. Acquired resistance results from a mutation in the bacterial chromosome or the acquisition of extra-chromosomal DNA.^[28] The spread of antibiotic resistance mechanisms occurs through vertical transmission of inherited mutations from previous generations and genetic recomination of DNA by horizontal genetic exchange.^[26] Antibiotic resistance exchanged between different bacteria by plasmids that carry genes which encode antibiotic resistance which may result in co-resistance to multiple antibiotics.^[26]^[29] These plasmids can carry different genes with diverse resistance mechanisms to unrelated antibiotics but because they are located on the same plasmid multiple antibiotic resistance to more than one antibiotic is transferred.^[29] Alternatively, cross-resistance to other antibiotics within the bacteria results when the same resistance mechanism is responsible for resistance to more than one antibiotic is selected for.^[29]

[edit] Antibiotic misuse

The overuse of antibiotics like penicillin and erythromycin which used to be one-time miracle cures were associated with emerging resistance since the 1950s.^[30]^[23] Therapeutic usage of antibiotics in hospitals has been seen to be associated with increases in multi-antibiotic resistant bacteria.^[30]

Common forms of antibiotic misuse include failure to take into account the patient's weight and history of prior antibiotic use when prescribing, since both can strongly affect the efficacy of an antibiotic prescription, failure to take the entire prescribed course of the antibiotic, failure to prescribe or take the course of treatment at fairly precise correct daily intervals (e.g. "every 8 hours" rather than merely "3x per day"), or failure to rest for sufficient recovery to allow clearance of the infecting organism. These practices may facilitate the development of bacterial populations with antibiotic resistance. Inappropriate antibiotic treatment is another common form of antibiotic misuse. A common example is the prescription and use of antibiotics to treat viral infections such as the common cold that have no effect.

In agriculture, associated antibiotic resistance with the non-therapeutic use of antibiotics as growth promoters in animals resulted in their restricted use in the UK in the 1970 (Swann report 1969). Currently there is a EU wide ban on the non-therapeutic use of antibiotics as growth promoters. It is estimated that greater than 70% of the antibiotics used in U.S. are given to feed animals (e.g. chickens, pigs and cattle) in the absence of disease.^[31] Antibiotic use in food animal production has been associated with the emergence of antibiotic-resistant strains of bacteria including Salmonella spp., Campylobacter spp., Escherichia coli, and Enterococcus spp.^[32]^[33] Evidence from some US and European studies suggest that these resistant bacteria cause infections in humans that do not respond to commonly prescribed antibiotics. In response to these practices and attendant problems, several organizations (e.g. The American Society for Microbiology (ASM), American Public Health Association (APHA) and the American Medical Association (AMA)) have called for restrictions on antibiotic use in food animal production and an end to all non-therapeutic uses.^{[citation needed]} However, delays in regulatory and legislative actions to limit the use of antibiotics are common, and may include resistance to these changes by industries using or selling antibiotics, as well as time spent on research to establish causal links between antibiotic use and emergence of untreatable bacterial diseases. Two federal bills (S.742^[34] and H.R. 2562^[35]) aimed at phasing out non-therapeutic antibiotics in US food animal production were proposed but not passed.^[34]^[35] These bills were endorsed by public health and medical organizations including the American Holistic Nurses’ Association, the American Medical Association, and the American Public Health Association (APHA).^[36] The EU has banned the use of antibiotics as growth promotional agents since 2003.^[37]

One study on respiratory tract infections found "physicians were more likely to prescribe antibiotics to patients who they believed expected them, although they correctly identified only about 1 in 4 of those patients".^[38] Multifactorial interventions aimed at both physicians and patients can reduce inappropriate prescribing of antibiotics. ^[39] Delaying antibiotics for 48 hours while observing for spontaneous resolution of respiratory tract infections may reduce antibiotic usage; however, this strategy may reduce patient satisfaction.^[40]

Excessive use of prophylactic antibiotics in travelers may also be classified as misuse.

[edit] Resistance modifying agents

One solution to combat resistance currently being researched is the development of pharmaceutical compounds that would revert multiple antibiotic resistance. These so called resistance modifying agents may target and inhibit MDR mechanisms, rendering the bacteria susceptible to antibiotics to which they were previously resistant. These compounds targets include among others

Efflux inhibition(Phe-Arg-β-naphthylamide)^[41]
Beta Lactamase inhibitors - Including Clavulanic acid and Sulbactam

[edit] Beyond antibiotics

The comparative ease of identifying compounds which safely cured bacterial infections was more difficult to duplicate in treatments of fungal and viral infections. Antibiotic research led to great strides in the knowledge of biochemistry, establishing large differences between the cellular and molecular physiology of the bacterial cell and that of the mammalian cell. This explained the observation that many compounds that are toxic to bacteria are non-toxic to human cells. In contrast, the basic biochemistries of the fungal cell and the mammalian cell are much more similar. This restricts the development and use of therapeutic compounds that attack a fungal cell, while not harming mammalian cells. Similar problems exist in antibiotic treatments of viral diseases. Human viral metabolic biochemistry is very closely similar to human biochemistry, and the possible targets of antiviral compounds are restricted to very few components unique to a mammalian virus.

Research into bacteriophages for use as antibiotics is presently ongoing. Several types of bacteriophage appear to exist that are specific for each bacterial taxonomic group or species.^{[citation needed]} Research into bacteriophages for medicinal use is just beginning, but has led to advances in microscopic imaging.^[42] While bacteriophages provide a possible solution to the problem of antibiotic resistance, there is no clinical evidence yet that they can be deployed as therapeutic agents to cure disease.^{[citation needed]}

Phage therapy, the use of particular viruses to attack bacteria, has been used in the past on humans in the US and Europe during the 1920s and 1930s, but these treatments had mixed results. With the discovery of penicillin in the 1940s, Europe and the US changed therapeutic strategies to using antibiotics. However, in the former Soviet Union phage therapies continued to be studied. In the Republic of Georgia, the Eliava Institute of Bacteriophage, Microbiology & Virology continues to research the use of phage therapy. Various companies and foundations in North America and Europe are currently researching phage therapies.^{[citation needed]} However, phage are living and reproducing; concerns about genetic engineering in freely released viruses currently limit certain aspects of phage therapy.

Bacteriocins are also a growing alternative to the classic small-molecule antibiotics ^[43]. Different classes of bacteriocins have different potential as therapeutic agents. Small molecule bacteriocins (microcins, for example, and lantibiotics) may be similar to the classic antibiotics; colicin-like bacteriocins are more likely to be narrow-spectrum, demanding new molecular diagnostics prior to therapy but also not raising the spectre of resistance to the same degree. One drawback to the large molecule antibiotics is that they will have relative difficulty crossing membranes and travelling systemically throughout the body. For this reason, they are most often proposed for application topically or gastrointestinally^[44]. Because bacteriocins are peptides, they are more readily engineered than small molecules^[45]. This may permit the generation of cocktails and dynamically improved antibiotics that are modified to overcome resistance.

Probiotics are another alternative that goes beyond traditional antibiotics by employing a live culture which may establish itself as a symbiont, competing, inhibiting, or simply interfering with colonization by pathogens. It may produce antibiotics or bacteriocins, essentially providing the drug in vivo and in situ, potentially avoiding the side effects of systemic administration.^{[citation needed]}

[edit] References

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^ "Drugs Affecting Birth Control Pills". http://www.wdxcyber.com/ncontr10.htm. Retrieved on 2008-02-17.
^ "Antibiotic and birth control". Yahoo answers. http://answers.yahoo.com/question/index;_ylt=AmTUUjVc3edfYh8cZaxmJ00jzKIX;_ylv=3?qid=20070524151339AAw8vfi. Retrieved on 2008-02-17.
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^ Stockley, IH (2002), Stockley's Drug Interactions. 6th ed. London: Pharmaceutical Press.
^ Cowen LE (March 2008). "The evolution of fungal drug resistance: modulating the trajectory from genotype to phenotype". Nat. Rev. Microbiol. 6 (3): 187–98. doi:10.1038/nrmicro1835. PMID 18246082.
^ ^a ^b Pearson, Carol (2007-02-28). "Antibiotic Resistance Fast-Growing Problem Worldwide". Voice Of America. http://voanews.com/english/archive/2007-02/2007-02-28-voa33.cfm. Retrieved on 2008-12-29.
^ Levy SB (October 1994). "Balancing the drug-resistance equation". Trends Microbiol. 2 (10): 341–2. PMID 7850197.
^ Luria SE, Delbrück M (November 1943). "Mutations of Bacteria from Virus Sensitivity to Virus Resistance". Genetics 28 (6): 491–511. PMID 17247100. PMC: 1209226. http://www.genetics.org/cgi/pmidlookup?view=long&pmid=17247100.
^ ^a ^b ^c Witte W (September 2004). "International dissemination of antibiotic resistant strains of bacterial pathogens". Infect. Genet. Evol. 4 (3): 187–91. doi:10.1016/j.meegid.2003.12.005. PMID 15450197.
^ Andersson DI (October 2006). "The biological cost of mutational antibiotic resistance: any practical conclusions?". Curr. Opin. Microbiol. 9 (5): 461–5. doi:10.1016/j.mib.2006.07.002. PMID 16890008.
^ ^a ^b Alekshun MN, Levy SB (March 2007). "Molecular mechanisms of antibacterial multidrug resistance". Cell 128 (6): 1037–50. doi:10.1016/j.cell.2007.03.004. PMID 17382878.
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^ Mellon, M et al. (2001) Hogging It!: Estimates of Antimicrobial Abuse in Livestock, 1st ed. Cambridge, MA: Union of Concerned Scientists.
^ http://whqlibdoc.who.int/hq/1997/WHO_EMC_ZOO_97.4.pdf (accessed Nov 12, 2008)
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^ ^a ^b GovTrack.us. S. 742--109th Congress (2005): Preservation of Antibiotics for Medical Treatment Act of 2005, GovTrack.us (database of federal legislation) <http://www.govtrack.us/congress/bill.xpd?bill=s109-742> (accessed Nov 12, 2008)
^ ^a ^b GovTrack.us. H.R. 2562--109th Congress (2005): Preservation of Antibiotics for Medical Treatment Act of 2005, GovTrack.us (database of federal legislation) <http://www.govtrack.us/congress/bill.xpd?bill=h109-2562> (accessed Nov 12, 2008)
^ http://www.acpm.org/2003051H.pdf (accessed Nov 12, 2008)
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^ Ong S, Nakase J, Moran GJ, Karras DJ, Kuehnert MJ, Talan DA (2007). "Antibiotic use for emergency department patients with upper respiratory infections: prescribing practices, patient expectations, and patient satisfaction". Annals of emergency medicine 50 (3): 213–20. doi:10.1016/j.annemergmed.2007.03.026. PMID 17467120.
^ Metlay JP, Camargo CA, MacKenzie T, et al (2007). "Cluster-randomized trial to improve antibiotic use for adults with acute respiratory infections treated in emergency departments". Annals of emergency medicine 50 (3): 221–30. doi:10.1016/j.annemergmed.2007.03.022. PMID 17509729.
^ Spurling G, Del Mar C, Dooley L, Foxlee R (2007). "Delayed antibiotics for respiratory infections". Cochrane database of systematic reviews (Online) (3): CD004417. doi:10.1002/14651858.CD004417.pub3. PMID 17636757.
^ B. Marquez. (2005). Bacterial efflux systems and efflux pumps inhibitors. Biochimie87 1137–1147
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^ Kirkup BC (2006). "Bacteriocins as oral and gastrointestinal antibiotics: theoretical considerations, applied research, and practical applications". Curr. Med. Chem. 13 (27): 3335–50. doi:10.2174/092986706778773068. PMID 17168847.
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[edit] External links

Wikimedia Commons has media related to: Antibiotics

Antibiotic News from Genome News Network (GNN)
JAAPA: New antibiotics useful in primary care
A new method for controlling bacterial activity without antibiotics - Research conducted at the Hebrew University
BURDEN of Resistance and Disease in European Nations
Antibiogram technique video
European Surveillance of Antimicrobial Consumption (ESAC)

[edit] Resources

[show]

Antibacterials: protein synthesis inhibitors (J01A, J01B, J01F, J01G)

[show]

Antibacterials: cell wall disruption (J01C-J01D)

[show]

Antibacterials: nucleic acid inhibitors (J01E, J01M)

[show] v • d • e Antibacterials: others (J01X)

Other/ungrouped	Xibornol · Clofoctol · Methenamine · Mandelic acid · Nitroxoline · Mupirocin

[show] v • d • e Major drug groups

Gastrointestinal tract/metabolism (A)	stomach acid (Antacids, H₂ antagonists, Proton pump inhibitors) • Antiemetics • Laxatives • Antidiarrhoeals/Antipropulsives • Anti-obesity drugs • Anti-diabetics • Vitamins • Dietary minerals

Blood and blood forming organs (B)	Antithrombotics (Antiplatelets, Anticoagulants, Thrombolytics/fibrinolytics) • Antihemorrhagics (Platelets, Coagulants, Antifibrinolytics)

Cardiovascular system (C)	cardiac therapy/antianginals (Cardiac glycosides, Antiarrhythmics, Cardiac stimulants) Antihypertensives • Diuretics • Vasodilators • Beta blockers • Calcium channel blockers • renin-angiotensin system (ACE inhibitors, Angiotensin II receptor antagonists, Renin inhibitors) Antihyperlipidemics (Statins, Fibrates, Bile acid sequestrants)

Skin (D)	Emollients • Cicatrizants • Antipruritics • Antipsoriatics • Medicated dressings

Reproductive system (G)	Hormonal contraception • Fertility agents • SERMs • Sex hormones

Endocrine system (H)	Hypothalamic-pituitary hormones • Corticosteroids (Glucocorticoids, Mineralocorticoids) • Sex hormones • Thyroid hormones/Antithyroid agents

Infections and infestations (J, P)	Antibiotics • Antifungals • Antimycobacterials (Tuberculosis treatment, Leprostatic agents) • Antivirals • Vaccines • Antiparasitics (Antiprotozoals, Anthelmintics)

Malignant disease (L01-L02)	Anticancer agents (Antimetabolites, Alkylating, Spindle poisons, Antineoplastic, Topoisomerase inhibitors)

Immune disease (L03-L04)	Immunomodulators (Immunostimulators, Immunosuppressants)

Muscles, bones, and joints (M)	Anabolic steroids • Anti-inflammatories (NSAIDs) • Antirheumatics • Corticosteroids • Muscle relaxants • Bisphosphonates

Brain and nervous system (N)	Anesthetics (General, Local) • Analgesics • Antimigraines • Anticonvulsants • Mood stabilizers • Antiparkinson drugs Psycholeptics (Anxiolytics, Antipsychotics, Hypnotics/Sedatives) • Psychoanaleptics (Antidepressants, Stimulants/Psychostimulants)

Respiratory system (R)	Decongestants • Bronchodilators • Cough medicines • H₁ antagonists

Sensory organs (S)	Ophthalmologicals • Otologicals • Ophthalmological preparations • Otological preparations

Other ATC (V)	Antidotes • Contrast media • Radiopharmaceuticals • Dressings

Retrieved from "http://en.wikipedia.org/wiki/Antibiotic"

Categories: Antibiotics | Greek loanwords

2009-02-24T23:51:00.001-08:00

Use of antibiotics

Because antibiotics are usually working on a very specific process, a mutation may occur in the bacterial strain allows the emergence of bacteria that are 'immune' to the antibiotics. That is, the antibiotics are usually given in doses that cause the bacteria die quickly in the time period and a slightly longer so that the mutation does not occur. The use of antibiotics that 'responsibility' only opportunity to open the type of bacteria that the emergence of 'immune'.

Use of antibiotics in agriculture as antibakteri generally considered to be limited because of expensive, but in biotechnology pemakaiannya wide to select cells containing the new genes. Practice the use of antibiotics is sharply criticized by environmental activists because of concern will be the emergence of antibiotic resistance of pests.

2009-02-24T23:50:00.001-08:00

Various antibiotics

Antibiotics can be classified based on the target compound and the work order kimiawinya. There are six groups of antibiotics [1] viewed from the target or targets of (name of the example given by the English spelling of the name has not been all in indonesian, indonesian or doubt it):

* Inhibitor bacterial cell wall synthesis, including the penicillin, Polypeptide and Cephalosporin, for example, ampicillin, penicillin G;
* Inhibitor transcript and replication, including the Quinolone, for example, rifampicin, actinomycin D, nalidixic acid;
* Inhibitor of protein synthesis, including many types of antibiotics, particularly from the Macrolide, Aminoglycoside, and Tetracycline, for example, gentamycin, chloramphenicol, kanamycin, streptomycin, tetracycline, oxytetracycline;
* Inhibitor cell membrane function, such as ionomycin, valinomycin;
* Inhibitor other cell functions, such as sulfa or sulfonamida groups, such as oligomycin, tunicamycin, and
* Antimetabolit, such as azaserine.

2009-02-24T23:47:00.001-08:00

Historical discovery of antibiotics, modern short

Discovery of antibiotics occurred in 'accidentally' when Alexander Fleming, in the year 1928, forget to clean sediaan bacteria on petri cup and leaving it in the wash rack along the weekend. On Monday, when the petri bowls will be cleaned, he saw some kapang has grown in the media and the kapang around the 'net' of bacteria that meet the media before. Because the fact is interested, he conducted research for more kapang, which is in fact Penicillium chrysogenum syn. P. notatum (kapang young blue found on this easy bread left some humid days). He then obtained positive results in testing the influence of extracts of the bacteria that kapang collection. Extracts from it are finding it the first natural antibiotics: penicillin G.

The findings antibakteri effect of Penicillium previously known by researchers from the Institut Pasteur in France at the end of the 19th century, but the result is not recognized by the institution itself and not published.

Antibiotics

2009-02-24T23:42:00.000-08:00

Antibiotic compound is a multitude, both natural and synthetic, which has the effect or stop a pressing process in the biochemistry of organisms, especially in the process of infection by bacteria. The use of antibiotics, especially regarding the treatment of infection, although in biotechnology and genetic engineering is also used as a means of selection against mutan or transforman. Antibiotics such as working with a pesticide or cut off a chain metabolism, is the only target bacteria. Antibiotics with different disinfectant because of how it works. Desifektan kill bacteria by creating environments that are not reasonable for the bacteria to live.

Unlike the previous treatment of infection, using poisons such as strychnine, antibiotics dijuluki "magic bullet": the aim of medicine without a master's wound. Antibiotics are not effective to handle due to virus infection, fungus, or other nonbakteri, and every variety of antibiotics are very effective against them in various types of bacteria. Antibiotics that have zero gram negative bacteria or gram-positive, there are more that have a spectrum luas.efektif it also depends on the location of infection and the ability of antibiotics to reach the location.

Oral antibiotics (which is eaten) is easy to use if effectively, and antibiotics intravena (through infus) is used for more serious cases. Sometimes antibiotics can be used locally, such as eye drops and cream

HIV

2008-08-12T22:24:00.001-07:00

HIV, the human immunodeficiency virus, is the virus that causes AIDS, a debilitating and deadly disease of the human immune system. HIV is one of the world's most serious health problems: at the end of 2001, more than 40 million people worldwide were infected with HIV and living with the virus or AIDS. The World Health Organization estimates that about 20 million people have died from AIDS since the infection was first described in 1981. Nearly 500,000 of those deaths have occurred in the United States. Although there is no cure for the disease, therapies exist that reduce the symptoms of AIDS and can extend the life spans of HIV-infected individuals. Researchers are also pursuing protective vaccines, but a reliable vaccine might still require years to develop.

Hiv and Aids

HIV infects certain cells and tissues of the human immune system and takes them out of commission, rendering a person susceptible to a variety of infections and cancers. These infections are caused by so-called opportunistic agents, pathogens that take advantage of the compromised immune system but that would be unable to cause infection in people with a healthy immune system. Rare cancers such as Kaposi's sarcoma also take hold in HIV-infected individuals. The collection of diseases that arise because of HIV infection is called acquired immune deficiency syndrome, or AIDS. HIV is classified as a lentivirus ("lenti" means "slow") because the virus takes a long time to produce symptoms in an infected individual.

Hiv Life Cycle: Entering Cells

Like a typical virus, HIV infects a cell and appropriates the host's cellular components and machinery to make many copies of itself. The new viruses then break out of the cell and infect other cells. HIV stores its genetic information on an RNA molecule rather than a DNA chromosome. This is a distinguishing characteristic of retroviruses, which are viruses that must first convert their RNA genomes into DNA before they can reproduce.

Each HIV virion (viral particle) is a small sphere composed of several layers. The external layer is a membrane coat, or envelope, obtained from the host cell in which the particle was made. Underneath this membrane lies a shell made from proteins, called a nucleocapsid. Inside the protein shell are two copies of the virion's RNA genome and three kinds of proteins, which are used by the virion to establish itself once inside the cell that it infects.

Two proteins, called gp120 and gp41, enable the virion to recognize the type of cell to enter. These proteins project from the HIV membrane coat. Gp120 binds to two specific proteins found on the target cell's surface (these target-cell proteins are called receptors). The first receptor, CD4, is found on immune system cells known as CD4 T cells, and also sometimes on two cell types known as macrophages and dendritic cells. The immune system uses CD4 T cells in the initial step in making antibodies against infectious agents. After binding to CD4, the HIV protein called gp120 binds with a second cell membrane protein, commonly referred to as the co-receptor. The co-receptor can be one of many different proteins, depending on the cell type. The two most common are CXCR4, which is normally found on CD4 T cells, and CCR5, a receptor found on CD4 T cells as well as on certain macrophages and dendritic cells. In the absence of HIV, CXCR4 and CCR5 allow these immune system cells to respond to chemical signals, but when HIV infects the cells, the HIV commandeers their usage. In some cases, individuals have a mutation in their co-receptor that prevents HIV from entering their cells.

Once gp120 has bound to both the CD4 receptor and co-receptor, the gp41 protein fuses HIV's membrane envelope with the cellular membrane, injecting the virus into the target cell. Once in the cytoplasm, the viral protein shell opens up and releases the viral proteins—a reverse transcriptase, a viral integrase, and a protease—along with the viral RNA strands. The reverse transcriptase copies the RNA strands into DNA. The viral integrase then helps insert the DNA copies into the cell's chromosome. At this point, the virus is called a provirus, and the life cycle halts. The provirus may remain dormant in the cell's chromosome for months or years, waiting for the T cell to become activated by the immune system.

Hiv Life Cycle: Reproduction

When the immune system recruits T cells to fight an infection, the T cells start producing many proteins. Along with the normal cellular protein products, a T cell carrying an HIV provirus also produces HIV proteins. The first HIV proteins made are called Tat and Rev. Tat encourages the cellular machinery to copy HIV's proviral DNA into RNA molecules. These RNA molecules are then processed in the nucleus to become templates for several of the HIV proteins, some of whose functions are not well understood.

Rev, on the other hand, ushers the HIV's RNA molecules from the nucleus, where they are being reproduced, into the host cell's cytoplasm. Early in HIV reproduction, with only a few RNA molecules from which to make protein, a small quantity of Rev is made. Therefore, most of the RNA molecules remain in the nucleus long enough to get processed. As time passes, however, and Tat continues to instigate RNA production, more Rev is made. A higher amount of Rev protein increases the speed with which RNA molecules are ejected from the nucleus. These RNA molecules, which have undergone little or no processing, become templates to make different HIV proteins. The newer proteins are made in long chains that require trimming before they become functional. One of the proteins in the chain is the protease, the protein that trims. Other proteins include those that make up the protein shell, the reverse transcriptase, and integrase.

After the newly created proteins are processed to the right size, they form new virions by first assembling into a shell, then drawing in two unprocessed RNA molecules and filling up the remaining space with integrase, protease, and replicase. The new virions bud from the host-cell membrane, appropriating some of that membrane to form an outer coat in the process. The mature virus particles are now ready to infect other cells.

Hiv's Immune-System Impairment Mechanism

One of the most disastrous effects of HIV infection is the loss of the immune system's CD4 T cells. These cells are responsible for recognizing foreign invaders to a person's body and initiating antibody production to ward off the infection. Without them, people are susceptible to a variety of diseases. HIV destroys the T cells slowly, sometimes taking a decade to destroy a person's immunity. However, in all the time before an HIV-infected individual shows any symptoms, the virus has been reproducing rapidly. The lymph tissue, the resting place for CD4 T cells, macrophages, and dendritic cells, becomes increasingly full of HIV, and viral particles are also released into the bloodstream.

HIV's main target is the population of CD4 T cells within a host's body. HIV kills them in one of three ways. It kills them directly by reproducing within them, then breaking them upon exit; it kills them indirectly by causing the cells to "commit suicide" by inducing apoptosis; or it kills them indirectly by triggering other immune cells to recognize the infected T cell and kill it as part of the immune system's normal function.

As infected T cells die, the immune system generates more to take their place. As new T cells become infected, they are either actively killed or induced to commit suicide. Meanwhile, the HIV virus is not completely hidden from the immune system. As with any infectious agent, HIV presents its proteins to the immune system, which develops antibodies against it. This antibody production, however, is hampered by the fact that HIV mutates rapidly, changing the proteins it displays to the immune system. With each new protein, the immune system must generate new antibodies to fight the infection. Thus, an HIV infection is a dramatic balance between a replicating, ever changing virus and the replenishing stores of T cells that are fighting it. Unfortunately, the immune system, without therapeutic intervention, eventually loses the battle.

Once the CD4 T cells are depleted, the immune system can no longer ward off the daily bombardment of pathogens that all human organisms experience. Common infectious agents thus overwhelm the system, and HIV patients become susceptible to a variety of "opportunistic" diseases that take advantage of the body's reduced ability to fight them off. AIDS doctors report at least twenty-six different opportunistic diseases specific to HIV infection. These include unusual fungal infections such as thrush. The chickenpox virus may come out of dormancy, manifesting itself as the painful disease known as shingles. An obscure form of pneumonia, called pneumocystis pneumonia, is also common in AIDS patients. In addition, patients can acquire cancers such as B-cell lymphoma, which is a cancer of the immune system. Doctors generally consider patients with fewer than 200 CD4 T cells per cubic milliliter of blood as having AIDS. (In contrast, a healthy person counts more than 1,000.)

Anti-Hiv Drug Therapy

Drugs that interfere with viral replication can slow down HIV disease. Early trials relied on the administration of one drug at a time. While patients' health improved and their T cell count rose, in time HIV mutated enough to render the drugs ineffective. Since 1995, however, doctors have found that rotating patients through three different drugs in very high doses significantly improves the health of AIDS patients. Known as "highly active antiretroviral therapy" (HAART), this therapeutic approach also reduces the amount of HIV circulating in the bloodstream to nearly undetectable levels. People infected with HIV who are treated by HAART are now living longer, healthier lives than ever before.

Targeting Life-Cycle Points

Drugs meant to knock out HIV target the activities of two HIV proteins, the reverse transcriptase and the protease. HAART requires drugs of both types. Drugs called protease inhibitors prevent the viral protease from trimming down the large proteins made late during infection. Without those proteins, the viral shell cannot be assembled. In addition, the proteins that reproduce HIV's genetic information, the reverse transcriptase and the integrase, are not functional.

Drugs that inhibit the reverse transcriptase prevent it from copying the RNA into DNA. These drugs work early in the life cycle of HIV. Reverse transcriptase inhibitors include azidothymidine (AZT), whose structure resembles the DNA nucleotide thymine. When reverse transcriptase builds DNA with AZT instead of thymine, the AZT caps the growing DNA molecule and halts DNA production, due to AZT's slight difference in structure from the thymine that DNA production requires.

Injection Drug Use and Hiv Infection

2008-08-12T22:22:00.000-07:00

Injection drug use (IDU) contributes to considerable illness burden in both developed and developing countries. Transmission of blood-borne pathogens (e.g., HIV, hepatitis B and C virus, Human T-Cell Lymphotrophic viruses I and II, and malaria) occurs primarily through direct sharing of needles or multi-person use of syringes. More recent studies suggest potential additional risks posed by shared use of injection paraphernalia (e.g., cookers, cotton, water), which is especially a concern with respect to transmission of hepatitis B and C viruses.

Human immunodeficency virus/acquired immunodeficiency syndrome (HIV/AIDS) and injection drug use can be considered as two intertwining epidemics. Socioeconomic, legal, and cultural factors and migration contribute to the emergence of drug injection. Injection drug use has been reported in 144 countries worldwide, among which 128 have detected HIV among injection drug users (IDUs). Although IDUs presently account for 5 to 10 percent of cumulative adult HIV infections worldwide, injection drug use is the predominant mode of HIV transmission in most of Western and Eastern Europe, North Africa, the Middle East, and increasingly in parts of Asia. Taking into account direct transmission among IDUs through sharing of contaminated injection equipment, and indirect transmission to sexual partners and offspring, injection drug use accounts for 44 percent of reported AIDS cases in Europe and nearly one-third of cases in the United States and the Southern Cone of South America. In the United States, approximately half of all new HIV infections are among IDUs. In Canada, the proportion of AIDS cases attributable to injection drug use is steadily increasing.

IDU-associated HIV epidemics are characterized by a high degree of regional and local heterogeneity. Explosive epidemics have occurred in both developing and developed countries or regions, with documented HIV incidence rates reaching as high as 20 to 30 percent per year. Early examples of HIV epidemics among IDUs were documented in Manipur, India Milan, Italy, Bangkok, Thailand, and New York City, suggesting that once HIV prevalence reaches a threshold of approximately 10 percent, it can surpass 40 to 50 percent within one to four years. More recently, Vancouver, Canada, witnessed an HIV outbreak with incidence reaching 18.6 per 100 person-years, despite an extended period of low stable HIV prevalence and a high-volume needle exchange program. In the Ukraine, over 100,000 HIV infections occurred in a single year, mostly due to sharing of injection equipment. These examples serve to illustrate the extent to which IDU-associated HIV epidemics can occur with startling speed. In such cases, subsequent spread to heterosexual non-IDU populations is almost imminent, which underscores the need for swift prevention measures.

In contrast, Australia and the United Kingdom have essentially averted widespread transmission of HIV among drug users. These prevention successes did not occur by chance. The early introduction of interventions such as widespread legal access to sterile injection equipment and expansion of methadone maintenance treatment programs likely spared these regions from the tragedies described above. Preventive strategies to curtail HIV transmission among IDUs are discussed in more detail below.

Preventive Strategies to Decrease Transmission of Blood-Borne Disease

Several interventions have been developed to reduce the spread of blood-borne disease among IDUs. These include programs that promote sterile syringe acquisition, drug abuse treatment, network-oriented interventions, and community outreach. These programs are briefly summarized.

Since sterile syringes are not accessible, affordable, or legal in the majority of countries that report injection drug use, the fundamental mechanism for reducing parenteral HIV transmission among IDUs is to provide unrestricted access to sterile syringes and to promote their one-time use. Examples are syringe exchange programs (SEPs), syringe vending machines, and enabling IDUs' access to syringes through pharmacies. These interventions are consistent with the concept of harm reduction, which aims to reduce the negative consequences associated with injection drug use among persons who cannot or will not cease injecting, and their surrounding community. At SEPs, IDUs exchange sterile syringes for potentially contaminated ones. A large body of international literature suggests that SEPs can be effective in reducing the incidence of HIV, Hepatitis B, and Hepatitis C, as well as needle sharing. No evidence exists to suggest that SEPs increase drug use or crime. At many SEPs, IDUs can receive condoms, referrals to HIV testing and drug treatment programs, and screening for STDs and tuberculosis. Unfortunately, in many U.S. states where SEPs operate illegally due to syringe paraphernalia laws, these critical ancillary services are less likely to be offered. In many developing countries, even when SEPs have been successfully introduced, severe fiscal restraints limit their ability to consistently offer services to a large number of IDUs.

Drug abuse treatment, and methadone maintenance in particular, has been associated with reduced injection frequency as well as declines in needle sharing, sexual risk behaviors, and HIV seroconversion. These studies support the notion that drug abuse treatment can be effective as primary HIV/AIDS prevention. Other opiate agonist therapies that are undergoing evaluation include substitution with buprenorphine, naltrexone and levo-alpha acetylmethadol (LAAM). Clinical trials have also evaluated the prescription of heroin under continuous medical surveillance, for example, in Switzerland. However, in cities where cocaine and methamphetamine are the main drugs of abuse, little is available in terms of drug abuse treatment. In North America, less that 25 percent of IDUs are receiving drug treatment at any given time, which signals an urgent need for expanded drug treatment services, including but not restricted to methadone maintenance. Other treatmentoriented initiatives that require expansion and evaluation include programs to prevent relapse from abstinence, interim treatment of drug users on waiting lists, interventions to refer SEP attenders into treatment, and development of substitution therapies for drug users addicted to stimulants.

Network and community-level strategies that modify social norms surrounding needle sharing constitute also valuable prevention tools. Network-based strategies of HIV prevention are based upon the personal networks of IDUs. Personal networks include people an IDU may have a social relationship with: an injecting partner, a sex partner, a family member, and so on. Studies have shown that personal network-based interventions can decrease needle sharing, decrease use of shooting galleries, and increase bleach disinfection.

Community-based outreach is characterized by utilization of former IDUs and/or peers to create a liaison between the drug using community and HIV education/treatment. In the United States, outreach has been shown to impact HIV risk by decreasing the frequency of drug use and reuse of needles and increasing use of bleach for purposes of disinfection. M. S. Kumar and colleagues have shown that community-based out-reach may also be effective in an international setting. They demonstrated significant decreases in needle use frequency and needle sharing among IDUs involved in outreached efforts as compared to IDUs not involved in outreach efforts in Madras, India. D. C. Des Jarlais has shown that community outreach is a crucial component held in common by five cities that have consistently maintained low stable HIV prevalence rates among IDU populations.

Prospects for the Future

In several cities that experienced early HIV epidemics among IDUs (e.g., Milan, Italy; Geneva, Switzerland; Amsterdam, the Netherlands; and New York City), HIV prevalence has declined. This has been attributed to AIDS-related mortality, pre-AIDS mortality, improvements in HIV treatments, migration, diminishing size of some IDU populations (e.g., Amsterdam), and reduced HIV incidence as a probable consequence of combinations of the above interventions. However, in the presence of high background HIV prevalence, even low levels of needle sharing can give rise to a relatively high number of new infections. In Amsterdam, large declines in injection risk (i.e., syringe borrowing, lending, and reusing) occurred from 1986 to 1991, and annual HIV incidence declined from 8 percent to 4 percent. However, van Ameijden and colleagues reported no further reductions occurred thereafter, suggesting that a minimum level of injecting risk may persist that is difficult to prevent. Since risk reduction rather than risk elimination appears to be a realistic goal, studies are needed to determine minimum levels of acceptable injection risk for specific regions, based on a thorough understanding of local risk behaviors, HIV prevalence and incidence, mixing patterns of susceptibles, and the estimated impact of interventions. This will require collaboration across the disciplines of epidemiology, behavioral science, and biostatistics.

Apart from the aforementioned strategies of HIV prevention among IDUs, a core prevention strategy that has yet to receive adequate attention is interventions that discourage transition from noninjection to injection drug use. The rationale for this approach is that the prevalence of hepatitis B and C surpasses 50 percent among new initiates to injection drug use within one year after initiation.

There is also evidence to suggest that risk factors for HIV seroconversion among IDUs may differ significantly by gender. For example, among male IDUs, injection-related risks and homosexual/bisexual activity appear to play a predominant role, whereas among females, sexual risks are paramount. These findings suggest that prevention programs should be gender-specific as well as being ethnoculturally and locally sensitive. Future studies should pay special attention to patterns of sexual behaviors of drug users in an effort to develop practical interventions.

In summary, the characteristics of IDU-associated HIV epidemics and interventions that have been effective in reducing IDUs' risk behaviors include access to sterile injecting equipment, methadone maintenance treatment, communitybased outreach, and peer network interventions. Unfortunately, in many settings the implementation of these proven interventions is often delayed due to lack of political will or inadequate resources. The delicate balance between an epidemic that is averted and one that is merely delayed argues against complacency in the realm of prevention. These obstacles will need to be over-come if HIV epidemics among drug user populations are to be controlled or prevented.

vitamin

2008-08-12T22:21:00.000-07:00

Definition

Vitamins are organic components in food that are needed in very small amounts for growth and for maintaining good health. The vitamins include vitamin D, vitamin E, vitamin A, and vitamin K, or the fat-soluble vitamins, and folate (folic acid), vitamin B₁₂, biotin, vitamin B₆, niacin, thiamin, riboflavin, pantothenic acid, and vitamin C (ascorbic acid), or the water-soluble vitamins. Vitamins are required in the diet in only tiny amounts, in contrast to the energy components of the diet. The energy components of the diet are sugars, starches, fats, and oils, and these occur in relatively large amounts in the diet.

Most of the vitamins are closely associated with a corresponding vitamin deficiency disease. Vitamin D deficiency causes rickets, a disease of the bones. Vitamin E deficiency occurs only very rarely, and causes nerve damage. Vitamin A deficiency is common throughout the poorer parts of the world, and causes night blindness. Severe vitamin A deficiency can result in xerophthalamia, a disease which, if left untreated, results in total blindness. Vitamin K deficiency results in spontaneous bleeding. Mild or moderate folate deficiency is common throughout the world, and can result from the failure to eat green, leafy vegetables or fruits and fruit juices. Folate deficiency causes megaloblastic anemia, which is characterized by the presence of large abnormal cells called megaloblasts in the circulating blood. The symptoms of megaloblastic anemia are tiredness and weakness. Vitamin B₁₂ deficiency occurs with

Essential Vitamins
Vitamin	What It Does For The Body
Vitamin A (Beta Carotene)	Promotes growth and repair of body tissues; reduces susceptibility to infections; aids in bone and teeth formation; maintains
	smooth skin
Vitamin B-1 (Thiamin)	Promotes growth and muscle tone; aids in the proper functioning of the muscles, heart, and nervous system; assists in digestion of
	carbohydrates
Vitamin B-2 (Riboflavin)	Maintains good vision and healthy skin, hair, and nails; assists in formation of antibodies and red blood cells; aids in carbohydrate,
	fat, and protein metabolism
Vitamin B-3 (Niacinamide)	Reduces cholesterol levels in the blood; maintains healthy skin, tongue, and digestive system; improves blood circulation; increases
	energy
Vitamin B-5	Fortifies white blood cells; helps the body's resistance to stress; builds cells
Vitamin B-6 (Pyridoxine)	Aids in the synthesis and breakdown of amino acids and the metabolism of fats and carbohydrates; supports the central nervous
	system; maintains healthy skin
Vitamin B-12 (Cobalamin)	Promotes growth in children; prevents anemia by regenerating red blood cells; aids in the metabolism of carbohydrates, fats, and
	proteins; maintains healthy nervous system
Biotin	Aids in the metabolism of proteins and fats; promotes healthy skin
Choline	Helps the liver eliminate toxins
Folic Acid (Folate, Folacin)	Promotes the growth and reproduction of body cells; aids in the formation of red blood cells and bone marrow
Vitamin C (Ascorbic Acid)	One of the major antioxidants; essential for healthy teeth, gums, and bones; helps to heal wounds, fractures, and scar tissue; builds
	resistance to infections; assists in the prevention and treatment of the common cold; prevents scurvy
Vitamin D	Improves the absorption of calcium and phosphorous (essential in the formation of healthy bones and teeth) maintains nervous
	system
Vitamin E	A major antioxidant; supplies oxygen to blood; provides nourishment to cells; prevents blood clots; slows cellular aging
Vitamin K (Menadione)	Prevents internal bleeding; reduces heavy menstrual flow

the failure to consume meat, milk or other dairy products. Vitamin B₁₂ deficiency causes megaloblastic anemia and, if severe enough, can result in irreversible nerve damage. Niacin deficiency results in pellagra. Pellagra involves skin rashes and scabs, diarrhea, and mental depression. Thiamin deficiency results in beriberi, a disease resulting in atrophy, weakness of the legs, nerve damage, and heart failure. Vitamin C deficiency results in scurvy, a disease that involves bleeding. Specific diseases uniquely associated with deficiencies in vitamin B₆, riboflavin, or pantothenic acid have not been found in the humans, though persons who have been starving, or consuming poor diets for several months, might be expected to be deficient in most of the nutrients, including vitamin B₆, riboflavin, and pantothenic acid.

Some of the vitamins serve only one function in the body, while other vitamins serve a variety of unrelated functions. Hence, some vitamin deficiencies tend to result in one type of defect, while other deficiencies result in a variety of problems.

Description

Vitamin treatment is usually done in three ways: by replacing a poor diet with one that supplies the recommended dietary allowance, by consuming oral supplements, or by injections. Injections are useful for persons with diseases that prevent absorption of fat-soluble vitamins. Oral vitamin supplements are especially useful for persons who otherwise cannot or will not consume food that is a good vitamin source, such as meat, milk or other dairy products. For example, a vegetarian who will not consume meat may be encouraged to consume oral supplements of vitamin B₁₂.

Treatment of genetic diseases which impair the absorption or utilization of specific vitamins may require megadoses of the vitamin throughout one's lifetime. Megadose means a level of about 10-1,000 times greater than the RDA. Pernicious anemia, homocystinuria, and biotinidase deficiency are three examples of genetic diseases which are treated with megadoses of vitamins.

dysmenorrhea

2008-08-12T22:20:00.001-07:00

Dysmenorrhea (or dysmenorrhoea), cramps or painful menstruation, involves menstrual periods that are accompanied by either sharp, intermittent pain or dull, aching pain, usually in the pelvis or lower abdomen.

Painful menstruation affects approximately 50% of menstruating women, and 10% are incapacitated for up to 3 days. Painful menstruation is the leading cause of lost time from school and work among women of childbearing age. This pain may precede menstruation by several days or may accompany it, and it usually subsides as menstruation tapers off.

Although some pain during menstruation is normal, excessive pain is not. Dysmenorrhea refers to menstrual pain severe enough to limit normal activities or require medication. It may coexist with excessively heavy blood loss (menorrhagia).

Primary dysmenorrhea refers to menstrual pain that occurs in otherwise healthy women (Wright et al. 2003). This type of pain is not related to any specific problems with the uterus or other pelvic organs.
Secondary dysmenorrhea is menstrual pain that is attributed to some underlying disease process or structural abnormality either within or outside the uterus (for example, pelvic inflammatory disease, leiomyoma, endometriosis, adhesions, adenomyosis, uterine displacement, or a retroverted uterus). Endometriosis is the most common cause of dysmenorrhea associated with a disease process and is frequently misdiagnosed.

The incidence of menstrual pain is greatest in women in their late teens and 20s, then declines with age. Some women experience increased menstrual pain in their late 30s and 40s as their endocrine systems prepare for menopause by decreasing hormone levels and thus fertility. It does not appear to be affected by childbearing. An estimated 10 percent to 15 percent of women experience monthly menstrual pain severe enough to prevent normal daily function at school, work, or home.

Risk factors

The majority of women will suffer this degree of dysmenorrhea at least once during their reproductive years. Increased risk is associated with younger age, and past medical history of any of the conditions associated with secondary dysmenorrhea.

Primary:
- Nulliparity (having never given birth)
- Obesity
- Cigarette smoking
- Positive family history
Secondary:
- Pelvic infection
- Sexually transmitted diseases
- Endometriosis

Primary Dysmenorrhea

Pathophysiology

Primary dysmenorrhea occurs during regular ovulatory cycles. Women with primary dysmenorrhea have increased activity of the uterine muscle with increased contractility and increased frequency of contractions. Prostaglandins are released during menstruation due to destruction of the endometrial cells and the resultant release of their contents.

Release of prostaglandins and other inflammatory mediators in the uterus (womb) is thought to be a major factor in primary dysmenorrhea (Wright et al. 2003). Prostaglandin levels have been found to be much higher in women with severe menstrual pain than in women who experience mild or no menstrual pain. Drugs which inhibit the production of prostaglandins, such as the non-steroidal anti-inflammatory drugs (NSAIDs) Naproxen, Ibuprofen and Mefenamic Acid, can provide relief for the discomfort and other associated symptoms of excessive prostaglandin release, such as nausea, vomiting, and headache.

Clinical Features

The cramping associated with dysmenorrhea usually begins a few hours before the start of bleeding and may continue for a few days. The pain is usually described as being in the lower abdomen, possibly radiating to the thighs and lower back. Other symptoms associated with primary dysmenorrhea are nausea and vomiting, fatigue, diarrhoea, lower backache, and headache.

Treatment

Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen and naproxen, are very effective in the treatment of primary dysmenorrhea (Andreoli et al. 2004). As earlier stated, their effectiveness comes from their ability to inhibit prostaglandin synthesis. However, many NSAIDs can cause gastrointestinal upset as a side effect. Patients who cannot take most common NSAIDs may be prescribed a cyclo-oxygenase-2 (COX2) inhibitor.

Oral contraceptives are second-line therapy unless a woman is also seeking contraception, then they would become first-line therapy. Oral contraceptives are 90% effective in improving primary dysmenorrhea and work by reducing menstrual blood volume and suppressing ovulation. It may take up to 3 months for the oral contraceptives to become effective. Norplant and Depo-provera are also effective since these methods often induce amenorrhea.

Alternative treatments

For the 10% of patients who do not respond to NSAIDs and/or oral contraceptives, a wide range of alternative therapies have been proven effective, including transcutaneous electrical nerve stimulation (TENS), acupuncture, omega-3 fatty acids, transdermal nitroglycerin, thiamine, and magnesium supplements.^{[citation needed]}

Chiropractic care has been an effective treatment approach (Chapman-Smith, 2000). Treating subluxations in the spine may cause the nerves leaving the spine to be less aggravated and so decrease symptoms of dysmenorrhea, as well as other symptoms such as chronic stomach aches and headaches. However, the Cochrane Review of 2007-04-19 ^[1] states "Authors' conclusions: Overall there is no evidence to suggest that spinal manipulation is effective in the treatment of primary and secondary dysmenorrhea."

Accupuncture is used to try to treat dysmenorrhea and studies have shown that it "reduced the subjective perception of dysmenorrhea" (Jun 2004). However, the small number of studies leaves doubt about the effectiveness of acupuncture for gynaecological conditions (White 2003).

Secondary Dysmenorrhea

Pathophysiology

The mechanisms causing the pain of secondary dysmenorrhea are varied and may or may not involve prostaglandins. Some causes of secondary dysmenorrhea are endometriosis, pelvic inflammation, leiomyoma, adenomyosis, ovarian cysts, and pelvic congestions (Hacker et al. 2004). The presence of an IUD (intrauterine device) for contraception may also be a potential cause of menstrual pain, although they usually lead to pelvic pain only around the time of insertion. Some women also find that use of internally-worn menstrual products, such as tampons and menstrual cups, exacerbate menstrual cramps and pain.

Clinical Features

The symptoms of secondary dysmenorrhea vary with the underlying cause, but generally the pain associated with secondary dysmenorrhea is not limited to the time around menses as with primary dysmenorrhea. Also, secondary dysmenorrhea is less related to the onset of bleeding in menstruation, is seen in older women, and is associated with other symptoms like infertility.

Treatment

The most effective treatment of secondary dysmenorrhea is the identification and treatment of the underlying cause of the pain, although the relief provided by NSAIDs is often helpful.

The first line of treatment is medical (e.g., prostaglandin synthetase inhibitors, hormonal contraception, danazol, progestins). If possible, the underlying disorder or anatomic abnormality is corrected, thus relieving symptoms. Dilation of a narrow cervical os may give 3 to 6 months of relief (and allows diagnostic curettage if needed). Myomectomy, polypectomy, or dilation and curettage may be needed. Interruption of uterine nerves by presacral neurectomy and division of the sacrouterine ligaments may help selected patients. Hypnosis may be useful.

Endometriosis is a common cause of secondary dysmenorrhea. In fact, approximately 24% of women who complain of pelvic pain are subsequently found to have endometriosis. This condition is often associated with infertility. If pain relief is the goal, medical options include hormonal contraception, danazol, progestational agents, and GnRH agonists.

diarrheA

2008-08-12T22:19:00.001-07:00

Description

Diarrhea is the abnormal increase of liquid in stool and increase in the frequency of passing stool (defecation). The person with diarrhea has watery or loose stool more than three times a day. Other symptoms include cramping, pain, feeling the urge to defecate, irritation of the skin around the anus (perianal), and inability to control defecation (fecal incontinence). Approximately 10% of the patients with advanced cancer suffer from diarrhea. Diarrhea lasting fewer than two weeks is called "acute diarrhea," and diarrhea lasting for longer than two months is called "chronic diarrhea."

Diarrhea is a debilitating condition that can significantly affect quality of life. Diarrhea can prevent patients from participating in social activities and going to work. Persons with diarrhea fear soiling their clothing or bed linens, a fear that prevents them from leaving home. Loss of sleep due to nighttime diarrhea can cause fatigue, which ultimately affects the patient's ability to function normally. Uncontrolled diarrhea can lead to chemical imbalances, loss of fluids (dehydration), and even death.

Causes

Although there are many causes of diarrhea, only those associated with cancer will be discussed. The most common cause of diarrhea in cancer patients is related to constipation or its treatment. Cancer patients may experience diarrhea as a result of their treatment, or it can be due to dietary changes, infections, hormone imbalances, digestion disorders, or inflammation. Treatment-related diarrhea can be caused by chemotherapy, hormone therapy, radiation therapy, biological response modifiers (drugs that improve the patient's immune system), or surgery. In addition, cancer patients may develop temporary lactose intolerance, which causes diarrhea.

Chemotherapy drugs kill the rapidly growing cancer cells. However, certain normal cells of the body are rapidly growing and they too are affected. Rapidly growing cells are found in the intestines, as well as other parts of the body. Diarrhea occurs as a result of injury to the cells of the intestine. These effects are temporary. Chemotherapy drugs, hormones, and biological response modifiers that frequently cause diarrhea include:

Dactinomycin
Daunorubicin
Diethylstilbestrol diphosphate
Doxorubicin
Fluorouracil
Flutamide
Hydroxyurea
Interferon
Interleukin-2 (aldesleukin)
Irinotecan
Methotrexate
Nitrosoureas
Thioguanine

Radiation therapy can cause diarrhea if the intestines are in the treatment field. Diarrhea results from the injury and destruction of the cells lining the intestines, which leads to a decrease in the uptake (absorption) of fluids and an increase in the speed with which stool moves through the intestines. Radiation therapy can cause diarrhea, and other intestinal problems, many months or years after treatment has been completed.

Diarrhea usually develops within one week following pretreatment (chemotherapy and irradiation) for bone marrow transplantation. This diarrhea usually disappears within two weeks. Also, bone marrow transplant patients with graft-versus-host disease develop severe diarrhea.

Treatments

Prevention

There are some measures that can prevent diarrhea. Patients who are receiving abdominal radiation therapy can be put into certain positions to minimize exposure of healthy intestines to radiation. Diarrhea caused by chemotherapy cannot be prevented; however, the administration of atropine during treatment with irinotecan may prevent diarrhea. Patients should stop taking dietary supplements, as these can cause diarrhea.

There are many dietary changes that can be made to prevent or reduce diarrhea. Foods to avoid include:

whole grain breads and cereals
fresh or frozen fruits (except banana)
dried fruits
fruit juices with pulp and prune juice
raw vegetables
canned onions, corn, olives, pickles, and Brussels sprouts
fatty foods
dried beans
rich desserts
milk and milk products
alcohol and caffeinated coffee and tea
spicy foods
fried foods

Management

Of the utmost importance in the treatment of diarrhea is the replacement of fluids lost by frequent, watery stools. The patient should drink six to eight glasses of fluid daily, including clear broth, ginger ale (without the fizz), water, weak tea, and commercial formulas that contain sugars and minerals (electrolytes). Patients with severe diarrhea may need intravenous fluid replacement either at home or in the hospital.

Diarrhea can cause the perianal skin to become irritated and painful; therefore, it needs to be cleaned thoroughly after each bout of diarrhea. Baby wipes or a mild soap with water can be used to clean the irritated skin. The area should be patted dry and occasionally exposed to air. Taking a sitz bath (sitting in a bathtub of shallow water) with lukewarm water may relieve the discomfort. Petroleum jelly or other type of barrier cream may be used.

The patient should eat small, frequent meals. Foods and drinks should be taken at room temperature. Foods that can help control diarrhea include:

bananas
applesauce
boiled white rice
tapioca
white bread
plain pasta
creamed cereals
eggs
potatoes (without skin; mashed or baked)
fish
chicken or turkey (without skin)

There are some medications that can slow down the movement of stool through the intestines and increase intestinal water absorption. The patient may need a combination of drugs and/or dose adjustments to achieve relief. A physician should be consulted before any over-the-counter antidiarrheal medications are taken. Anti-diarrheal medications include:

Atropine sulfate with diphenoxylate HCl (Lomotil)
Codeine phosphate
Loperimide HCl (Imodium-AD)
Octreotide phosphate (Sandostatin)

These medications should not be used if infection as the cause of diarrhea has not been eliminated.

Patients who are experiencing diarrhea due to graft-versus-host disease will continue to take their immunosuppressant drugs. They may also be treated with corticosteroids and antidiarrheal medications.

Alternative and Complementary Therapies

Peppermint tea, chamomile tea, valerian capsules, or aloe vera juice may reduce cramping and intestinal spasms. An Ayurvedic physician may recommend taking equal parts of yogurt and water with fresh ginger, or a powder of beleric myrobalan fruit. Ginger capsules may relieve intestinal spasms and pain. Glutamine supplements may speed up the healing process and relieve irritated intestines.

anti- depressant

2008-08-12T22:18:00.001-07:00

Definition

Antidepressant drugs are medicines that relieve symptoms of depressive disorders.

Description

Antidepressant agents act by increasing the levels of excitatory neurostransmitters. The main types of antidepressant drugs in use today are:

tricyclic antidepressants, such as amitriptyline (Elavil), imipramine (Tofranil), nortriptyline (Pamelor)
selective serotonin reuptake inhibitors (SSRIs or serotonin boosters), such as fluoxetine (Prozac), paroxetine (Paxil), and sertraline (Zoloft)
monoamine oxidase inhibitors (MAO inhibitors), such as phenelzine (Nardil), and tranylcypromine (Parnate)
tetracyclic compounds and atypical antidepressants which do not fall into any of the above categories

Selective serotonin reuptake inhibitors maintain levels of the excitatory neurohormone serotonin in the brain. They do not alter levels of norepinephrine. These have become the drugs of choice for a variety of psychiatric disorders, primarily because of their low incidence of severe side effects as compared with other drugs in this therapeutic class. SSRIs show similar actions and side effect profiles, but may vary in duration of action.

Tricyclic compounds, identified by their chemical structure containing three carbon rings, are an older class of antidepressants. Although generally effective, they have a high incidence of anticholinergic effects, notably dry mouth and dry eyes, which can cause discomfort. They also cause cardiac arrythmias. Because tricyclics act on both serotonin and norepinephrine, they may have some value in treatment of patients who fail to respond to SSRIs. Drugs in this class are often available at low prices, which may be significant when cost is a major factor in treatment. They have also been found useful in control of some neurologic pain syndromes.

Tricyclic antidepressants are similar, but may vary in severity of side effects, most notably the degree of sedation and the extent of the anticholinergic effects.

Tetracyclic compounds and atypical antidepressants are chemically distinct from both the major groups and each other. Although maprotilene (no brand name, marketed in generic form only) and mirtazepine (Remeron) are similar in chemical structures, they differ in their balance of activity on serotonine and norepinephrine levels.

Monoamine oxidase inhibitors (phenelzine [Nardil], tranylcypromine [Parnate]) have largely been supplanted

Antidepressant Drugs
Brand Name (Generic Name)	Possible Common Side Effects Include:
Desyrel (trazodone hydrochloride)	Allergic skin reactions, blurred vision, decreased appetite, fluid retention, headache
Effexor (venlafaxine hydrochloride)	Diarrhea, dizziness, gas, headache, insommia, rash, vomiting
Elavil (amitriptyline hydrochloride)	Constipation, idzziness, high blood pressure, fever, nausea, rash, weight gain or loss
Nardil (phenelzine sulfate)	Dry mouth, fatigue, headache, muscle spasms, tremors
Norpramin (desipramine hydrochloride)	Blurred vision, cramps, hallucinations, hair loss, vomiting
Pamelor (nortriptyline hydrochloride)	Diarrhea, fatigue, headache, decreased coordination
Paxil (paroxetine hydrochloride)	Cold symptoms, drowsiness, nervousness, stomach pain
Prozac (fluoxetine hydrochloride)	Bronchitis, drowsiness, fatigue, nausea, tremors
Sinequan (doxepin hydrochloride)	Bruising, constipation, fluid retention, itching, increased heartbeat
Surmontil (trimipramine maleate)	Disorientation, flushing, headache, nausea, vomiting
Tofranil (imipramine hydrochloride)	Bleeding sores, fever, hives, decreased coordination
Travil	Asthma, diarrhea, dizziness, fatigue, seizures
Wellbutrin (bupropion hydrochloride)	Agitation, dry mouth, headache, nausea, rash
Zoloft (sertraline)	Diarrhea, fainting, gas, headache, nervousness

in therapy because of their high risk of severe adverse effects, most notably severe hypertension. They act by inhibiting the enzyme monoamine oxidase, which is responsible for the metabolism of the stimulatory neurohormones norepinephrine, epinephrine, dopamine, and serotonin. The MAOIs are normally reserved for patients who are resistant to safer drugs. Two drugs, eldepryl (Carbex, used in treatment of Parkinson's disease) and the herb, St. John's wort, have some action against monoamine oxidase B, and have shown some value as anti-depressants. They do not share the same risks as the non-selective MAO inhibitors.

All antidepressant agents, regardless of their structure, have a slow onset of action, typically three to five weeks. Although adverse effects may be seen as early as the first dose, significant therapeutic improvement is always delayed. Similarly, the effects of antidepressants will continue for a similar length of time after the drugs have been discontinued.

paracetamol

2008-08-12T22:15:00.002-07:00

Definition

Acetaminophen is a medicine used to relieve pain and reduce fever.

Purpose

Acetaminophen is used to relieve many kinds of minor aches and pains, including headaches, muscle aches, backaches, toothaches, menstrual cramps, arthritis, and the aches and pains that often accompany colds. It is suitable for control of pain following minor surgery, or for post-surgical pain after the need for stronger pain relievers has been reduced. Acetaminophen is also used in combination with narcotic analgesics both to increase pain relief and reduce the risk that the narcotics will be abused.

Description

This drug is available without a prescription. Acetaminophen (APAP) is sold under various brand names, including Tylenol, Panadol, Aspirin-Free Anacin, and Bayer Select Maximum Strength Headache Pain Relief Formula. Many multi-symptom cold, flu, and sinus medicines also contain acetaminophen. Persons are advised to check the ingredients listed on the container to see if acetaminophen is included in the product.

Acetaminophen is also included in some prescription-only combinations. These usually contain a narcotic in addition to acetaminophen; it is combined with oxycodone in Percocet, and is included in Tylenol with Codeine.

Studies have shown that acetaminophen relieves pain and reduces fever about as well as aspirin. But differences between these two common drugs exist. Acetaminophen is less likely than aspirin to irritate the stomach. However, unlike aspirin, acetaminophen does not reduce the redness, stiffness, or swelling that accompany arthritis.

Recommended Dosage

The usual dosage for adults and children age 12 and over is 325–650 mg every four to six hours as needed. No more than 4 g (4,000 mg) should be taken in 24 hours. Because the drug can potentially harm the liver, people who drink alcohol in large quantities should take considerably less acetaminophen and possibly should avoid the drug completely.

For children ages six to 11 years, the usual dose is 150–300 mg, three to four times a day. People are advised to check with a physician for dosages for children under six years of age.

Precautions

A person should never take more than the recommended dosage of acetaminophen unless told to do so by a physician or dentist.

Because acetaminophen is included in both prescription and non-prescription combinations, it is important to check the total amount of acetaminophen taken each day from all sources in order to avoid taking more than the recommended maximum dose.

Patients should not use acetaminophen for more than 10 days to relieve pain (five days for children) or for more than three days to reduce fever, unless directed to do so by a physician. If symptoms do not go away, or if they get worse, the patient should contact a physician. Anyone who drinks three or more alcoholic beverages a day should check with a physician before using this drug and should never take more than the recommended dosage. People who already have kidney or liver disease or liver infections should also consult with a physician before using the drug. Women who are pregnant or breastfeeding should also consult with a physician before using acetaminophen.

Smoking cigarettes may interfere with the effectiveness of acetaminophen. Smokers may need to take higher doses of the medicine, but should not take more than the recommended daily dosage unless told to do so by a physician.

Many drugs can interact with one another. People should consult a physician or pharmacist before combining acetaminophen with any other medicine, and they should not use two different acetaminophen-containing products at the same time, unless instructed by a physician or dentist.

Some products, such as Nyquil, contain acetaminophen in combination with alcohol. While these products are safe for people who do not drink alcoholic beverages, people who consume alcoholic drinks regularly, even in moderation, should use extra care before using acetaminophen-alcohol combinations.

Acetaminophen interferes with the results of some medical tests. Before having medical tests done, a person should check to see whether taking acetaminophen would affect the results. Avoiding the drug for a few days before the tests may be necessary.

Side Effects

Acetaminophen causes few side effects. The most common one is lightheadedness. Some people may experience trembling and pain in the side or the lower back. Allergic reactions do occur in some people, but they are rare. Anyone who develops symptoms such as rash, swelling, or difficulty breathing after taking acetaminophen should stop taking the drug and get immediate medical attention. Other rare side effects include yellow skin or eyes, unusual bleeding or bruising, weakness, fatigue, bloody or black stools, bloody or cloudy urine, and a sudden decrease in the amount of urine.

Overdoses of acetaminophen may cause nausea, vomiting, sweating, and exhaustion. Very large overdoses can cause liver damage. In case of an overdose, a person is advised to get immediate medical attention.

Interactions

Acetaminophen may interact with a variety of other medicines. When this happens, the effects of one or both of the drugs may change or the risk of side effects may be greater. Among the drugs that may interact with acetaminophen are alcohol, non-steroidal anti-inflammatory drugs (NSAIDs) such as Motrin, oral contraceptives, the anti-seizure drug phenytoin (Dilantin), the blood-thinning drug warfarin (Coumadin), the cholesterol-lowering drug cholestyramine (Questran), the antibiotic Isoniazid, and zidovudine (Retrovir, AZT). People should check with a physician or pharmacist before combining acetaminophen with any other prescription or nonprescription (over-the-counter) medicine.

seizures

2008-08-12T22:15:00.001-07:00

Definition

Antiepileptic drugs are medicines that reduce the frequency of epileptic seizures.

This class of drugs includes some drugs that have other uses as well. Phenobarbital is a barbiturate. Barbiturates were once widely used as sleeping pills and are still used in anesthesia for surgery. Clonazepam, clorazepate, and diazepam are members of the benzodiazepine group of drugs and are best known for their use as tranquilizers. Phenytoin is used both to control epileptic seizures and to control irregular heart beats.

Description

There are several different types of epilepsy. Different drugs work best on different types of epilepsy. Following is a list of some of the drugs and their uses:

* topamax (Topiramate), keppra, and ACTH: for infantile spasms (IS)
* ativan: for status epilepticas
* phenobarbital: widely used for tonic-clonic but effective in all forms of epilepsy
* phenytoin (Dilantin): used in tonic-clonic and psychomotor epilepsy
* ethosuximide (Zarontin): used to treat absence seizures
* methsuximide (Celontin): used to treat absence seizures
* zonisamide (Zonegran): used to treat partial seizures
* clonazepam (Klonopin): a benzodiazepine, used to treat absence, myoclonic, and akinetic seizures
* clorazepate (Tranxene): a benzodiazepine used to treat partial seizures
* diazepam (Valium): a benzodiazepine used for treatment of status epilepticus but effective against all forms of epilepsy
* primidone (Mysoline, Myidone, Sertan): useful for tonic-clonic, psychomotor, and focal epilepsy
* valproic acid and sodium valproate (Depakene, Depakote): used to treat all types of generalized seizures
* carbamazepine (Carbatrol, Tegretol): used in treatment of tonic-clonic, mixed, and psychomotor seizures
* felbamate (Felbatol): used primarily in adults but may be used to treat seizures associated with Lennox-Gastaut syndrome
* oxcarbazepine (Trileptal): for treatment of complex-partial, simple-partial, and focal seizures
* lamotrigine (Lamictal): used primarily in adults to treat simple and complex partial seizures but may be used to treat seizures associated with Lennox-Gastaut syndrome in children

General Use

Although epilepsy is a collective term for a variety of different types of seizures, all forms of epilepsy start with a random discharge of nerve impulses into the brain. Antiepileptic drugs act by either raising the seizure threshold or by limiting the spread of impulses from one nerve to another inside the brain. As of 2004 the exact mechanism of action is not understood, but there are theories about how some of these drugs work.

Phenobarbital appears to act by slowing down all parts of the brain.

Hydantoins, the class that includes phenytoin, mephenytoin, and ethotoin, seem to work by reducing the flow of sodium into and out of nerve cells. This makes the cells less likely to send out spontaneous impulses, which are the beginning of an epileptic seizure.

Succinimides (ethosuximide, methsuximide, phensuximide) elevate the seizure threshold and make it harder for a nerve impulse to spread from one nerve to another.

Zonisamide may work in a manner similar to the hydantoins, by restricting sodium flow, but some studies contradict this theory.

Benzodiazepines may work by stimulating some brain chemicals that normally slow down nerve function, but the exact mechanism is not known.

Felbamate is similar to the tranquilizer meprobamate (Equanil, Miltown) and may work by blocking the effects of some of the brain chemicals that stimulate the nervous system.

Precautions

Antiepileptic drugs have a large number of side effects and possible adverse effects. To work best, the blood levels of drugs must be kept within a fairly narrow range. Patients should be seen by a qualified physician on a regular basis and, if required, have their blood tested routinely. Too high a blood level of these drugs is likely to cause toxic reactions, while a level that is too low may lead to seizures.

Side Effects

Most anticonvulsant medications cause some drowsiness and stomach upset. The following list gives some of the common adverse effects of the various classes of drugs. Parents should consult specific references for more comprehensive lists.

Barbiturates cause the following side effects:

* clumsiness
* dizziness
* constipation
* depression
* faintness

Benzodiazepines cause the following side effects:

* fatigue
* abnormal behavior which can include hallucinations and agitation
* slowed breathing and slowed heart rate
* increased or decreased appetite
* rash and itching

Hydantoins cause the following side effects:

* confusion
* dizziness
* growth of the gums
* severe skin reactions
* stuttering and trembling

Succinimides cause the following side effects:

* dizziness and loss of balance
* severe skin reactions
* depression
* headache
* aggressive behavior

Valproic acid and sodium valproate cause the following side effects:

* stomach and intestinal discomfort
* weight gain or loss
* hair loss
* menstrual bleeding changes
* trembling

Interactions

These drugs have many interactions. People should consult specific references for full information regarding the interactions of all drugs that may be used to treat epilepsy.

Phenobarbital and the hydantoins have a large number of other interactions, but most of the drugs involved are not commonly used in patients under the age of 18 years. The succinimides have no significant drug interactions.

Valproic acid and sodium valproate interact with many of the other drugs used to treat epilepsy. If valproates are added to an existing anti-epileptic drug regimen or other drugs are added to a regimen that contains valproate, additional dose adjustments will usually be needed.

Cimetidine (Tagamet) increases the effects of diazepam, clonazepam, and clorazepate.

Interaction Prevention

Because antiepileptic drugs have large numbers of adverse effects and drug interactions, they should be prescribed only by physicians who are experienced in their use. Parents should consult specific references for complete information on the drugs related to their child's case.

Best effects and lowest toxicity are achieved when the blood levels of these drugs are kept constant. Maintaining that constant level requires taking the drugs at the same time each day.

Excessive gum growth associated with the hydantoins can normally be prevented or minimized by good dental care.

Patients taking antiepileptic drugs should not receive additional medications without checking with a physician or pharmacist for possible drug interactions. This precaution includes over-the-counter remedies.

Parental Concerns

For liquid dosage forms, parents should always use a medicinal teaspoon or calibrated teaspoon. These are designed to deliver an exact amount of medication. Household teaspoons vary in size and should not be used for measuring medication.

Different dosage forms of the same drug may vary in their onset and duration of action. This fact is particularly relevant to phenytoin, which comes in liquid, chewable tablets, short-acting capsules and long-acting capsules. Patients should not switch from one dosage form to another without consulting their physician.

Because children may not be able to describe some of the symptoms associated with some of the adverse effects of these drugs, any evidence of change in behavior or activity should be discussed with the physician who prescribed the drug.

antiepileptic

2008-08-12T22:09:00.000-07:00

Definition

Antiepileptic drugs are medicines that reduce the frequency of epileptic seizures.

This class of drugs includes some drugs that have other uses as well. Phenobarbital is a barbiturate. Barbiturates were once widely used as sleeping pills and are still used in anesthesia for surgery. Clonazepam, clorazepate, and diazepam are members of the benzodiazepine group of drugs and are best known for their use as tranquilizers. Phenytoin is used both to control epileptic seizures and to control irregular heart beats.

Description

There are several different types of epilepsy. Different drugs work best on different types of epilepsy. Following is a list of some of the drugs and their uses:

topamax (Topiramate), keppra, and ACTH: for infantile spasms (IS)
ativan: for status epilepticas
phenobarbital: widely used for tonic-clonic but effective in all forms of epilepsy
phenytoin (Dilantin): used in tonic-clonic and psychomotor epilepsy
ethosuximide (Zarontin): used to treat absence seizures
methsuximide (Celontin): used to treat absence seizures
zonisamide (Zonegran): used to treat partial seizures
clonazepam (Klonopin): a benzodiazepine, used to treat absence, myoclonic, and akinetic seizures
clorazepate (Tranxene): a benzodiazepine used to treat partial seizures
diazepam (Valium): a benzodiazepine used for treatment of status epilepticus but effective against all forms of epilepsy
primidone (Mysoline, Myidone, Sertan): useful for tonic-clonic, psychomotor, and focal epilepsy
valproic acid and sodium valproate (Depakene, Depakote): used to treat all types of generalized seizures
carbamazepine (Carbatrol, Tegretol): used in treatment of tonic-clonic, mixed, and psychomotor seizures
felbamate (Felbatol): used primarily in adults but may be used to treat seizures associated with Lennox-Gastaut syndrome
oxcarbazepine (Trileptal): for treatment of complex-partial, simple-partial, and focal seizures
lamotrigine (Lamictal): used primarily in adults to treat simple and complex partial seizures but may be used to treat seizures associated with Lennox-Gastaut syndrome in children

General Use

Although epilepsy is a collective term for a variety of different types of seizures, all forms of epilepsy start with a random discharge of nerve impulses into the brain. Antiepileptic drugs act by either raising the seizure threshold or by limiting the spread of impulses from one nerve to another inside the brain. As of 2004 the exact mechanism of action is not understood, but there are theories about how some of these drugs work.

Phenobarbital appears to act by slowing down all parts of the brain.

Hydantoins, the class that includes phenytoin, mephenytoin, and ethotoin, seem to work by reducing the flow of sodium into and out of nerve cells. This makes the cells less likely to send out spontaneous impulses, which are the beginning of an epileptic seizure.

Succinimides (ethosuximide, methsuximide, phensuximide) elevate the seizure threshold and make it harder for a nerve impulse to spread from one nerve to another.

Zonisamide may work in a manner similar to the hydantoins, by restricting sodium flow, but some studies contradict this theory.

Benzodiazepines may work by stimulating some brain chemicals that normally slow down nerve function, but the exact mechanism is not known.

Felbamate is similar to the tranquilizer meprobamate (Equanil, Miltown) and may work by blocking the effects of some of the brain chemicals that stimulate the nervous system.

Precautions

Antiepileptic drugs have a large number of side effects and possible adverse effects. To work best, the blood levels of drugs must be kept within a fairly narrow range. Patients should be seen by a qualified physician on a regular basis and, if required, have their blood tested routinely. Too high a blood level of these drugs is likely to cause toxic reactions, while a level that is too low may lead to seizures.

Side Effects

Most anticonvulsant medications cause some drowsiness and stomach upset. The following list gives some of the common adverse effects of the various classes of drugs. Parents should consult specific references for more comprehensive lists.

Barbiturates cause the following side effects:

clumsiness
dizziness
constipation
depression
faintness

Benzodiazepines cause the following side effects:

fatigue
abnormal behavior which can include hallucinations and agitation
slowed breathing and slowed heart rate
increased or decreased appetite
rash and itching

Hydantoins cause the following side effects:

confusion
dizziness
growth of the gums
severe skin reactions
stuttering and trembling

Succinimides cause the following side effects:

dizziness and loss of balance
severe skin reactions
depression
headache
aggressive behavior

Valproic acid and sodium valproate cause the following side effects:

stomach and intestinal discomfort
weight gain or loss
hair loss
menstrual bleeding changes
trembling

Interactions

These drugs have many interactions. People should consult specific references for full information regarding the interactions of all drugs that may be used to treat epilepsy.

Phenobarbital and the hydantoins have a large number of other interactions, but most of the drugs involved are not commonly used in patients under the age of 18 years. The succinimides have no significant drug interactions.

Valproic acid and sodium valproate interact with many of the other drugs used to treat epilepsy. If valproates are added to an existing anti-epileptic drug regimen or other drugs are added to a regimen that contains valproate, additional dose adjustments will usually be needed.

Cimetidine (Tagamet) increases the effects of diazepam, clonazepam, and clorazepate.

Interaction Prevention

Because antiepileptic drugs have large numbers of adverse effects and drug interactions, they should be prescribed only by physicians who are experienced in their use. Parents should consult specific references for complete information on the drugs related to their child's case.

Best effects and lowest toxicity are achieved when the blood levels of these drugs are kept constant. Maintaining that constant level requires taking the drugs at the same time each day.

Excessive gum growth associated with the hydantoins can normally be prevented or minimized by good dental care.

Patients taking antiepileptic drugs should not receive additional medications without checking with a physician or pharmacist for possible drug interactions. This precaution includes over-the-counter remedies.

Parental Concerns

For liquid dosage forms, parents should always use a medicinal teaspoon or calibrated teaspoon. These are designed to deliver an exact amount of medication. Household teaspoons vary in size and should not be used for measuring medication.

Different dosage forms of the same drug may vary in their onset and duration of action. This fact is particularly relevant to phenytoin, which comes in liquid, chewable tablets, short-acting capsules and long-acting capsules. Patients should not switch from one dosage form to another without consulting their physician.

Because children may not be able to describe some of the symptoms associated with some of the adverse effects of these drugs, any evidence of change in behavior or activity should be discussed with the physician who prescribed the drug.

pharmacy

2008-08-12T22:08:00.001-07:00

There were but few who could claim any prior pharmaceutical training in all the colonies in the seventeenth century. By the end of the eighteenth century, however, and far into the nineteenth, four types of practitioners of pharmacy were identifiable. First was the physician who compounded and dispensed his own medicines and often kept a "Doctor's shop." Second was the apothecary who, like his English model, not only compounded and dispensed drugs, but also diagnosed and prescribed. Third was the druggist, later also to be called a pharmacist. The term "druggist" was originally applied to wholesalers but subsequently described one who compounded medicines in shops in which a major concern was pharmaceuticals and related items. Fourth was the merchant who took on a supply of drugs; many eventually evolved into pharmacists.

The Drugstore

The nineteenth-century American drugstore carried a full line of simples (mainly crude vegetable drugs) and chemicals with which pharmacists compounded and dispensed medicines, with or without a prescription. They were artisans who spread their own plasters and prepared pills, powders, tinctures, ointments, syrups, conserves, medicated waters, and perfumes. Economic necessity forced them to handle such commodities as confections, tobacco, paints, glass, groceries, spices, and liquor. They were thus commonly also merchants, and pharmacists often differed among themselves as to whether theirs was a trade or a profession.

By the mid-nineteenth century this artisanal role of pharmacists had begun to diminish. A pharmaceutical industry was providing medicines that pharmacists had previously made entirely by hand. There was a burgeoning growth of proprietary ("patent") medicines, flamboyantly advertised, with which pharmacists had to deal. Economic competition from department stores, groceries, and chain stores added to the pressure. Late in the century the competition—including that among pharmacists, for the "cut-rate" pharmacy shop had become ubiquitous—led to a number of plans to fix prices, but both these plans and the fair trade statutes of the mid-twentieth century fell afoul of federal antitrust laws.

One peculiarly American development was the drugstore soda fountain, which was an outcome of the pharmacist's knowledge of flavors and carbonated water. The pharmacist Elias Durand operated a soda fountain in his Philadelphia shop as early as 1825. American soft drinks, the colas particularly, had their beginnings in the drugstore. The soda fountain was not to disappear from the drugstore until the mid-twentieth century, when it gave way to more profitable alternative uses for the space.

Science and Technology

The great scientific and technological advances in the medical and biological sciences in the late nineteenth century transformed pharmacy in a number of ways. First, the old materia medica—still showing evidence of ancient lineage—increasingly gave way to new medications based on a better scientific understanding of the etiology of diseases and of the mechanisms of drug action. These medications were the products of synthetic and medicinal chemistry, new powerful tools. Second, in the twentieth century these new medications were largely the discoveries and innovations of the rapidly developing pharmaceutical industry and, moreover, were the products of research and manufacture that the individual pharmacist could not duplicate. This meant that the compounding of medicines by the pharmacist gave way to the dispensing of medications completely prepared by industry. By the 1970s only one percent of prescriptions required some combination or manipulation of ingredients. Third, the sciences gave impetus to the separation of pharmaceutical practice from medical practice.

Pharmacy Law

The training of the pharmacist was accomplished largely through the apprenticeship system and, in the absence of legal restrictions—a concomitant of Jacksonian democracy—it was possible for any persons to set themselves up as pharmacists. The first laws providing for the examination and licensing of pharmacists in an American jurisdiction were passed in Louisiana, where the Franco-Spanish tradition in pharmacy prevailed in regulations of the Territory of Orleans in 1808 and of the state in 1816. The few other such attempts before the Civil War, in three southern states and a few localities, were, in the prevailing democratic milieu, ineffectual.

Rhode Island passed the first modern state law for the examining and licensing of pharmacists in 1870. Pressure for such laws came from the American Pharmaceutical Association, founded in 1852, and from state and territorial pharmaceutical associations (of which there were forty-five and two, respectively, by 1900). As a consequence, forty-seven states had such laws by the end of the century. This legislation established state boards of pharmacy, composed originally of pharmacists. The boards, among other powers, examined candidates and imposed educational requirements that became more advanced as the colleges of pharmacy increased the depth and length of the pharmacy curricula. Following standards and accreditation requirements developed by the American Association of Colleges of Pharmacy (founded in 1900) and by the American Council on Pharmaceutical Education (founded in 1932), these curricula increased from two and three-year Graduate in Pharmacy (Ph.G.) and Pharmaceutical Chemist (Ph.C.) programs, to four-and five-year baccalaureate programs, and to six–year Doctor of Pharmacy (Pharm.D.) programs. In 1999 over 45 percent of all the pharmacy graduates in the country received the Pharm.D. degree as their first professional degree.

Under the American constitutional system it was state law that regulated pharmacy and imposed restrictions on the sales of poisons and abortifacients. The federal government first became involved in the regulation of pharmacy with the Pure Food and Drug Act of 1906. That legislation and its principal amendments (1912, 1938, 1952, and 1962) and the Harrison Narcotic Act of 1914 set the stage for what became the very close federal involvement in the control of drugs. "Legend drugs, " requiring a physician's prescription, and a list of "controlled dangerous substances" made the pharmacist subject to federal, as well as state, authority.

Pharmaceutical Education

Pharmaceutical education began in the United States with the founding of the Philadelphia College of Pharmacy (now the University of the Sciences in Philadelphia) in 1821.

The term"college" was intended at first to suggest only a society rather than a school, but the Philadelphia College offered lectures almost from the start. Local societies of pharmacy, also calling themselves colleges, were formed in Boston, New York City, Baltimore, Cincinnati, Chicago, and St. Louis, and all of them sooner or later engaged in pharmaceutical instruction. By 1900 about sixty programs were or had been in operation. The program of instruction in these institutions, especially in the good number that were private and proprietary, was indeed meager, consisting mainly of a series of lectures in the evening in rented rooms.

In 1868 the University of Michigan embarked upon a full program of scientific training in pharmacy, eventually developing a full-time, day program of two years. The University of Wisconsin followed suit in 1883 and nine years later it pioneered in offering a four-year program leading to a bachelor's degree. As noted, the length and the curricular requirements took off from there, reflecting new developments in the pharmaceutical sciences and the changing professional role of the pharmacist, both in and beyond the drugstore. The curriculum changes demanded by the doctorate included more attention to the humanities and emphasized clinical pharmacy and relatively new sciences like pharmacokinetics and pharmacotherapeutics. Externship programs in community, industrial, hospital, and clinical pharmacy became part of the curriculum.

The Changing Role of the Pharmacist

The plethora of new and complex medicines that industry was providing, along with the increasing demands for prescription drugs as the population aged, meant that pharmacists who dealt directly with the patient needed to be more than just artisans who compounded or dispensed drugs. Limited in their freedom of activity by the introduction of Medicaid and Medicare, the new managed care systems, and computerization, pharmacists found that their choice of drugs and their prices were no longer under their control. The pharmacist assumed a new, consultative role in health-care delivery that demanded knowledge of the drugs and their action in the body and the monitoring of the drug regimen of the patients.

The responsibility of the pharmacist in providing correct and effective medication and in preventing errors was evident in the great expansion of pharmacists into the health field beyond the drugstore. Hospital pharmacy goes back in the United States to before the Revolution; by 1942 hospital pharmacists had become so significant a part of the heath-care community that they formed the American Society of Hospital Pharmacists. As the twentieth century progressed, the practice of clinical pharmacy developed. In clinical pharmacy the pharmacist is responsible in a hospital situation for cooperating with the physician in monitoring the prescribed medications. Clinical and consulting pharmacists also are involved in other institutions, such as nursing homes and assisted living quarters. In recognition of the broader role of clinical and consultative pharmacy, the American Society of Hospital Pharmacists became the American Society of Health System Pharmacists in 1995.

Demographics and Infrastructure

The demography of pharmacy personnel changed quite rapidly in the late twentieth century. Beginning in 1985, more than half of each year's pharmaceutical degree recipients were women. In 1999 women graduates made up 63.5 percent of the total. The ethnicity of personnel was also changing. The percentage of white graduates fell from 86 percent in 1979 to 64 percent in 1999, while the percentage of Asian, Native Hawaiian, and Pacific Islanders rose from under 4 percent to over 18 percent in the same period. African Americans rose from 3.6 percent to 5.6 percent; Hispanics and Latinos declined from 3.8 percent to 3.7 percent.

The last decade of the twentieth century saw a drop in the total number of drugstore outlets from 58,642 in 1990 to 53,105 in 1999. The decline, however, was only among independent pharmacies. They went from 31,879 to 20,649, a decrease of 11,230 units in the decade. Chain stores, supermarket units, and mass merchandiser units all increased in number. One factor in the decline of independent pharmacies was the development of Pharmacy Benefit Management organizations (PBMs) and the accompanying growth of mail-order prescription services.

At the end of the twentieth century the National Community Pharmacists Association (founded as the National Association of Retail Druggists in 1898) still had a membership of 25,000. The American Society of Health-System Pharmacists had an equal number of members. Pharmacy had developed in two directions.

low back pain

2008-08-12T22:05:00.000-07:00

Definition

Low back pain (LBP) is a common complaint—second only to cold and flu as a reason why patients seek care from their family doctor. It may be a limited musculoskeletal symptom or caused by a variety of diseases and disorders that affect or extend from the lumbar spine. Low back pain is sometimes accompanied by sciatica, which is pain that involves the sciatic nerve and is felt in the lower back, the buttocks, the backs and sides of the thighs, and possibly the calves. More serious causes of LBP may be accompanied by fever, night pain that awakens a person from sleep, loss of bladder or bowel control, numbness, burning urination, swelling or sharp pain.

Description

Low back pain is a symptom that affects 80% of the general United States population at some point in life with sufficient severity to cause absence from work. As mentioned, it is the second most common reason for visits to primary care doctors, and is estimated to cost the American economy $75 billion every year. One third of the nation's disability related costs are associated with LBP, a condition primarily affecting individuals between the ages of 45–60.

The most common cause of low back pain is lumbar strain. The structures of the normal lumbar region of the spine include the lumbar vertebrae, discs between each vertebrae, ligaments, muscles and muscle tendons, the spinal cord within the vertebrae and nerves extending out-ward from the spine through vertebral foramina (openings in the bone). The lumbar vertebrae are distinct from the cervical (neck area) and thoracic (upper back) vertebrae, being generally thicker for greater weight bearing support, and resting atop the sacrum, the triangular shaped bone between the buttocks. The discs between each vertebrae of the spine cushion and absorb the shock that might otherwise be transmitted through the spine. Occasionally, the discs may "rupture" or herniate outward through their fibrous sheath, or covering, putting pressure on the nerves. Nerve pressure as sciatica (affecting the sciatic nerve) may be causative or additive to LBP. Nerve pain from other local organs may also be causative, in which case diagnosis and treatment is more involved, usually much more serious, and may indicate a life threatening condition.

Risks for low back pain are increased with fracture and osteoporosis, narrowing of the spinal canal within the vertebrae (stenosis), spinal curvatures, fibromyalgia, osteo- and rheumatoid arthritis, pregnancy, smoking, stress, age greater than 30, or disease or illness of the organs of the lower abdomen.

In addition to dividing low back pain into three categories based on duration of symptoms—acute, sub-acute or chronic—low back pain may be described as:

Localized. In localized pain the patient will feel soreness or discomfort when the doctor palpates, or presses on, a specific surface area of the lower back.
Diffuse. Diffuse pain is spread over a larger area and comes from deep tissue layers.
Radicular. The pain is caused by irritation of a nerve root and radiates from the area. Sciatica is an example of radicular pain.
Referred. The pain is perceived in the lower back, but actually is caused by inflammation or disease elsewhere, such as the kidneys or other structures of or near the lower abdomen including the intestines, appendix, bladder, uterus, ovaries or the testes.

Causes & Symptoms

Acute and Sub-Acute Pain

Lumbar strain or sprain is the most common cause of acute low back pain. It is pain that does not usually extend to the leg and usually occurs within 24 hours of heavy lifting or overuse of the back muscles. The pain is usually localized, and may be accompanied by muscle spasms or soreness to touch. The patient usually feels better when resting. Acute strain may follow a sudden movement, especially a lifting and simultaneous twisting motion, however injury is usually preceded by overuse or lack of exercise and tone especially of the opposing muscles (the abdominals, for example), improper use, long periods of sitting or standing in one position, poor vertebral alignments or conditions compromising nutrition of the supportive structures. Acute low back pain due to lumbar strain (approximately 60% of sufferers) usually resolves with a week with conservative therapies, including reducing but not eliminating all activity. Sub-acute pain is associated with a duration of 6–12 weeks, by which time 90% of persons suffering low back pain and injury return to work. This category accounts for one third of all disability related costs. LBP persisting beyond three months is considered chronic. Symptoms of acute LBP may be accompanied by stiffness (guarding), constipation, poor sleep and trouble finding a comfortable position, difficulties walking and other limits on normal range of motion.

Chronic Pain

Chronic low back pain has several different possible causes.

MECHANICAL. Chronic strain on the muscles of the lower back may be caused by obesity, pregnancy, or jobrelated stooping, bending, or other stressful postures. Construction, truck driving accompanied by vibration, jack hammering, sand blasting and other sources of chronic trauma and strain to the back or nerve pressure also contribute.

MALIGNANCY OR OTHER SERIOUS ILLNESS. Low back pain at night that is not relieved by lying down may be caused by a tumor in the cauda equina (the roots of the spinal nerves controlling sensation in and movement of the legs), or metastasized cancer that has spread to the spine from the prostate, breasts, or lungs. The risk factors for the spread of cancer to the lower back include a history of smoking, sudden weight loss, and age over 50. Kidney problems, such as kidney stones; ovarian and uterine problems, including fibroids, endometriosis, premenstrual water retention, and ovarian cysts; chronic constipation and sluggish or enlarged colon; benign tumors; bone fractures; aneurysm of the aorta; herpes zoster shingles; intra-abdominal infection, or, bleeding secondary to Coumadin therapy; osteomyelitis, tuberculosis of the spine (Pott's disease), and sepsis of the vertebral discs—all may be associated with pain to the lower back. Additional symptoms may include night sweats; being awakened at night by pain; weakness, numbness, muscle fatigue or poor coordination which progressively worsens; burning on urination; redness or swelling over the area of pain; changes in bowel or urinary patterns; and malaise.

ANKYLOSING SPONDYLITIS. Ankylosing spondylitis is a form of arthritis that causes chronic pain in the back. The pain is made worse by sitting or lying down, and improves when the patient gets up. It is most commonly seen in males between the ages of 16 and 35. Ankylosing spondylitis is often confused with mechanical back pain in its early stages. Other symptoms include morning stiffness, a positive family history, and positive lab results for HLA-B27 antigen (an autoimmune marker) and an increased sedimentation (Sed) rate of the blood. This condition may have food allergy related components, such as an allergy to wheat, worsened by drinking beer.

HERNIATED SPINAL DISK. Disk herniation is a disorder in which a spinal disk begins to bulge outward between the vertebrae. Herniated or ruptured disks are a common cause of chronic low back pain in adults. Pressure imposed on adjacent nerves results in pain that may worsen on movement, with coughing, sneezing or intraabdominal strain, and be accompanied by numbness of the skin in the area served by the nerve (dermatome). Deep tendon reflexes (DTRs) may be reduced, and the straight leg raising test may be positive. The crossed straight leg raising test, which is more specific to herniated disc, may also be positive.

PSYCHOGENIC. Back pain that is out of proportion to a minor injury, or that is unusually prolonged, may be associated with a somatoform disorder or other emotional disturbance. Psychosocial factors such as loss of work, job dissatisfaction, legal problems, financial compensation issues are some of the 'non-organic' factors that may be associated or causative. Symptoms of low back pain in this configuration are usually diffuse, non-localized, and may include other stress related symptoms. A set of five tests called the Waddell tests may be used to help diagnose LBP of psychogenic origin.

Low Back Pain With Leg Involvement

Low back pain that radiates down the leg usually indicates involvement of the sciatic nerve. The nerve can be pinched or irritated by herniated disks, tumors of the cauda equina (the end portion of the spine), abscesses in the space between the spinal cord and its covering, spinal stenosis, and compression fractures. Some patients experience numbness or weakness of the legs, as well as pain. There may be spasming of those muscles otherwise stimulated by the involved nerve, and a positive leg raising test.

Diagnosis

The diagnosis of low back pain can be complicated. Most cases are initially evaluated by primary care physicians or other health practitioners, rather than by specialists.

Initial Workup

PATIENT HISTORY. The doctor will ask the patient specific questions about the location of the pain, its characteristics, its onset, and the body positions or activities that make it better or worse. If the doctor suspects that the pain is referred from other organs, he or she may ask about a history of diabetes, peptic ulcers, kidney stones, urinary tract infections, heart murmurs, or other health issues. Age, family history, and previous medical history are also important. LBP in persons younger than 20 and older than 50 are apt to be associated with a more severe underlying condition or cause.

PHYSICAL EXAMINATION. The doctor will examine the patient's back and hips to check for conditions that require surgery or emergency treatment. The examination includes several tests that involve moving the patient's legs in specific positions to test for nerve root irritation or disk herniation. The flexibility of the lumbar vertebrae may be measured to rule out ankylosing spondylitis. Other physical tests include assessments of gait and posture, range of motion, and the ability to perform certain physical positions, coordinated movements. Reflex, sensory and motor tests may help the clinician screen for referral to a specialist, as needed. Diagnostic tests may be used, especially with persisting, chronic pain, for further work up, tests including X-ray, CATscan, MRI, and electromyelographs (EMGs).

RED FLAGS. The presence of certain symptoms warrant a more rapid progress to deeper diagnostic examination as to cause. These serious symptoms include, but are not limited to:

pain following violent injury, accident or trauma
constant pain that worsens
upper spinal pain
a history of cancer
being HIV positive
a history of steroid drug use or drug abuse
development of an obvious structural deformity
a history of rapid weight loss
unexplained fever, or nightsweats, with back pain
being younger than 20 and older than 50

Treatment

A thorough differential diagnosis is important before any treatment is considered. There are times when alternative therapies may be most beneficial, and other times when more invasive treatments are needed.

Chiropractic

Chiropractic treats patients by manipulating or adjusting sections of the spine. It is one of the most popular forms of alternative treatment in the United States for relief of back pain caused by straining or lifting injuries, and has been demonstrated through several randomized trials to be beneficial. Some osteopathic physicians, physical therapists, and naturopathic physicians also use spinal manipulation to treat patients with low back pain, along with work on soft tissue around the bones. Additional recommendations of shoe orthotics, exercise, cold packs to reduce and inhibit swelling immediately after injury followed one to two days later by hot packs and cold packs to stimulate healing, hydrotherapy, and life style adjustments may be recommended. Nutritional supplements known to be beneficial to joint repair and integrity, collagen support, and wound repair may also be recommended, including glucosamine sulfate, with or without chondroitin, MSM,, and a variety of mineral and vitamin cofactors.

Traditional Chinese Medicine

Practitioners of traditional Chinese medicine treat low back pain with acupuncture, acupressure, massage, and the application of herbal poultices. They may also use a technique called moxibustion which involves the use of glass cups, and heated air derived use of a burning braid or stick of herb with a distinctive aroma.

Herbal Medicine and Anti-Inflammatory Enzymatic Therapy

Herbal medicine can utilize a variety of antispasmodic and sedative herbs to help relieve low back pain due to spasm. For this purpose and easily available at a local healthfood store are herbs such as chamomile (Matricaria recutita), hops (Humulus lupus), passion flower (Passiflora incarnata), valerian (Valeriana officinale), and cramp bark (Viburnum opulus). Bromelain from pineapples has anti-inflammatory activity. Intake of fresh grape juice, preferably made from from dark grapes, on a daily basis at a time other than mealtime has also been found to be helpful. Minor backaches may be relieved with the application of a heating paste of ginger (Zingiber officinale) powder and water, allowed to sink in for 10 minutes, and followed by an eucalyptus rub.

Aromatherapy with soothing essential oils of blue chamomile, birch, rosemary, and/or lavender can be effective when rubbed into the affected area after a hot bath.

Homeopathy

Homeopathic treatment for acute back pain consists of various applications of Arnica (Arnica montana); as an oil or gel applied topically to the sore area or oral doses alone or in prepackaged combination products including other homeopathic such as St. John's wort (Hypericum perforatum), Rhus tox (Rhus toxicodendron) and Ruta (Ruta graveolens). Bellis perennis may be recommended for deep muscle injuries. Other remedies may be recommended based on the symptoms presented by the patient.

Body Work and Yoga

Massage and the numerous other body work techniques can be very effective in treating low back pain. Yoga, practiced regularly and done properly, can be combined with meditation or imagery to both treat and prevent future episodes of low back pain.

Allopathic Treatment

All forms of treatment of low back pain are aimed either at symptom relief or to prevent interference with the processes of healing. None of these methods appear to speed up healing.

Acute Pain

Acute back pain is treated with muscle relaxantsor nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen or aspirin. Applications of compresses using heat or cold also can be helpful to some patients. Patients are recommended by one source, do not worry, and to stay active. Acute LBP often resolves within a short time. Some patients may be prescribed opiod analgesics (pain relievers with codeine or codeine similars), however, statistics demonstrate no shortening of the healing period, as noted above. The use of muscle relaxants may increase risk of further damage, but they have been shown to be more effective than placebo (though no better than NSAIDS alone) in relieving acute pain. If the patient has not experienced some improvement after several weeks of treatment, the doctor will reinvestigate the cause of the pain.

Chronic Pain

Patients with chronic back pain are treated with a combination of medications, physical therapy, and occupational or lifestyle modification. The medications given are usually NSAIDs, although patients with hypertension, kidney problems, or stomach ulcers are advised not take these drugs. Patients who take NSAIDs for longer than six weeks are advised to be monitored periodically for complications. Chronic pain, by definition longer than three months in duration, may also prompt a more thorough diagnostic workup.

Physical therapy for chronic low back pain usually includes regular exercise for fitness and flexibility, and massage or application of heat if necessary. Lifestyle modifications include quitting smoking, weight reduction (if necessary), and evaluation of the patient's occupation or other customary activities. Good lift and bend mechanics may also be reviewed and counseled.

Patients with herniated disks may be treated surgically if the pain does not respond to medication. Vertebral fusion surgery may stiffen the spine, however, engineers of skyscrapers recognize the need of flexibility with height to preserve wind resistance: a fused spine may reduce capacity. A newer surgical procedure known as kyphoplasty, involving guided penetration of the back and cemented repair, may be indicated in pain due to vertebral fracture. Patients with chronic low back pain sometimes benefit from pain management techniques, including biofeedback, acupuncture, and chiropractic manipulation of the spine. Psychotherapy is recommended for patients whose back pain is associated with a somatoform, anxiety, or depressive disorder.

Low Back Pain With Leg Involvement

Treatment of sciatica and other disorders that involve the legs may include NSAIDs. Patients with longstanding sciatica or spinal stenosis that do not respond to NSAIDs may be treated surgically. Although some doctors use cortisone injections in trigger points and vertebral facet joints to relieve the pain, this form of treatment is still debated. Also debated are benefits due to spinal traction and transcutaneous (through the skin) electrical nerve stimulation.

Expected Results

The prognosis for most patients with acute low back pain is excellent. About 80% of patients recover completely in 4–6 weeks. The prognosis for recovery from chronic pain depends on the underlying cause.

Prevention

Low back pain due to muscle strain can be prevented by lifestyle choices, including regular physical exercise and weight control, avoiding smoking, and learning the proper techniques for lifting and moving heavy objects. Exercises designed to strengthen the muscles of the lower back and the opposing abdominals are also recommended. Simple actions can also help prevent low back pain, such as putting a small, firm cushion behind the lower back when sitting for long intervals, using a soft pillow for sleep that supports the lower neck without creating an unnatural angle for head and shoulder rest, using a swiveling desk chair with a postural support or stool that maintains the knees at a higher level than the hips, standing on flexible rubber mats to avoid the impact of concrete floors at places of employment for example, and wearing supportive, soft soled shoes, avoiding the use of high heels.

antiemetic

2008-08-12T22:02:00.001-07:00

Definition

Antiemetic drugs are drugs used to combat nausea and vomiting.

Purpose

Antiemetic drugs are used to prevent vomiting (emesis) in chemotherapy patients and postoperative patients. Aside from the difficulty of maintaining proper nutrition and a healthy weight, chronic vomiting can result in dehydration, which can be a medical emergency. Following are descriptions of many common antiemetic drugs in use as of 2004.

Description

Promethazine

Promethazine is also known as phenergan and mepergan. It is also used to treat motion sickness, reduce allergic symptoms, and for sedation. It is one of the drugs of the phenothiazine type. In addition to other qualities, it is an antihistamine.

Prochlorperazine

Prochlorperazine is also known as compazine. Like promethazine, it is a member of the class of phenothiazines. Unlike promethazine, however, prochlorperazine also belongs to the class of drugs known as antipsychotics, or neuroleptics. Antipsychotic drugs are used to treat psychoses and other psychiatric disorders. In addition to its use as an antiemetic and anti-psychotic drug, prochlorperazine is also used to treat non-psychotic anxiety.

Serotonin Receptor Antagonists

The serotonin receptor antagonists include granisetron (kytril), dolasetron (anzemet), and ondansetron (zofran). These drugs are used for postoperative nausea and emesis as well as nausea and vomiting associated with chemotherapy, and are often used in combination with a corticosteroid. Ondansetron is approved for nausea and vomiting associated with radiation therapy.

Neurokinin Receptor Antagonists

The Neurokinin receptor antagonists are a new class of antiemetics. Aprepitant (Emend) was approved in 2004 for use in cancer patients. It is used in combination with other antiemetics for relief of acute and delayed nausea and vomiting caused by high-dose chemotherapy, most often caused by the chemotherapy drug cisplatin.

Dronabinol

Dronabinol (marinol) is used to combat anorexia in AIDS patients, and emesis in cancer patients who haven't responded to other antiemetics. Marinol is the synthetic or extracted form of the active ingredient found in marijuana.

Other Antipsychotic (Neuroleptic) Drugs

The other neuroleptic (antipsychotic) drugs used to treat nausea and emesis are droperidol (inapsine), halo-peridol (haldol), chlorpromazine (thorazine), and perphenazine (trilafon). One other antipsychotic, triethylperazine (torecan or norzine), was used as an antiemetic, but is no longer widely available. Some of the antipsychotics are also used to treat aggressive or violent behavior or incontrollable hiccups (chlorpromazine). These drugs are similar to prochlorperazine in terms of their actions and potentially severe side effects.

Dosage

Promethazine

Promethazine is given in doses of 12.5 to 25 mg every 4 hours if injected into the muscle or as a suppository. As a syrup, 25 mg should be given every 4 to 6 hours. Doses for children vary by age, weight, and severity of condition.

Prochlorperazine

Generally, the dose is 5 to 10 mg, 3 to 4 times per day. However, the effect of medication varies widely from patient to patient, so the dose should be tailored to each individual. Prochlorperazine is available as a syrup, tablet, 25 mg slow-release capsule, and in injectable form.

Aprepitant

One 125-mg capsule is given by mouth one hour before chemotherapy begins. An 80-mg capsule is taken each morning for two days following the chemotherapy treatment.

Dronabinol

The effective dose of dronabinol varies widely from patient to patient and should be monitored and tested by the physician. The basic dose is 5mg/m2 given 4 to 6 times per day.

Precautions

Promethazine

Patients with cardiovascular disease or impaired liver function should either use this drug with caution or not at all. Children should also use this drug cautiously for two reasons. First, some side effects may suggest, or mask, underlying disease, such as Reye's syndrome. Second, large doses of this drug, or any antihistamine, may cause convulsions, hallucinations, or death in children. Patients taking this medication should not drive, operate heavy machinery, or engage in any hazardous activity while under the influence of this drug. This drug has not been established as safe for use during pregnancy, or in nursing mothers.

Prochlorperazine

Persons allergic to any other phenothiazine (such as promethazine) should not take prochlorperazine. Patients who have heart problems, glaucoma, or bone marrow depression should take this drug with caution, or not at all, and inform their physician of their condition. People who will be around high temperatures should also avoid this drug. In addition, those who experience seizures should be aware that administration of this drug makes seizures more likely.

Breast cancer patients may wish to avoid this drug because it increases levels of prolactin in the blood.

Increased prolactin may help some types of breast cancer to thrive.

Prochloroperazine, like promethazine, may mask symptoms of Reye's disease in children. It may also mask symptoms of intestinal obstructions or brain disease. In addition, children who are acutely ill, under two years of age, or under 20 pounds should not be given this drug.

This drug has not been established as safe for use during pregnancy and is found in the breast milk of lactating mothers. Therefore, caution should be used when administering this drug to pregnant women and extreme caution should be used when administering to nursing women.

Aprepitant

Patients should not drink grapefruit juice while taking aprepitant. The physician should be told if the patient is pregnant, breast feeding, or becomes pregnant while taking the drug.

Serotonin Receptor Antagonists

Patients with allergies to any drug in this category should not take any other drug in this category. Also, patients with hypokalemia, hypomagnesia, or certain heart problems should avoid taking these drugs. The effect of these drugs on the children or fetuses of nursing or pregnant mothers is not known, so they should be used with caution.

Dronabinol

Dronabinol is inadvisable for patients with a known allergy to either sesame oil or any part of the cannabis plant. Patients taking this drug should not drive, operate heavy machinery, or engage in hazardous tasks until used to this medication.

This medication also should be used cautiously, if at all, for persons with depression, mania, or schizophrenia, elderly patients, patients with cardiac disorders, and for pregnant and nursing women. It is especially inadvisable for nursing women, since marinol is concentrated in the breast milk.

Side Effects

Promethazine

Patients taking promethazine may experience a large number of side effects, including drowsiness, ringing in the ears, a lack of coordination, problems with vision, fatigue, euphoria, nervousness, tremors, seizures, a catatonic-like state, and hysteria. These effects are usually reversible. At high doses, patients may also exhibit extrapyramidal reactions. Extrapyramidal reactions can briefly be described as agitation (jitteriness, sometimes insomnia), muscle spasms, and/or pseudo-Parkinson's (a group of symptoms including, but not limited to, drooling, tremors, and a shuffling gait).

Patients may also experience rashes, asthma, jaundice, abnormally low production of white blood cells, and abnormalities in how fast or slow their heart beats. Patients may sometimes experience unusual side effects not known as typical for the medication they are taking. These should be reported to the physician.

Prochlorperazine

Prochlorperazine has many side effects, including low blood pressure, dizziness, blurred vision, skin reactions, and jaundice. Patients also may suffer jaw, neck, and back muscle spasms, slow or difficult speech, and difficulty swallowing, as well as rhythmic face, mouth, or jaw movements. However, the most severe side effects stem from damage to the brain after long-term use. These symptoms may be reversed by treating the patient with drugs effective in treatment of Parkinson's patients (except levodopa). A reduction or elimination in the amount of the antipsychotic medication may also be necessary to eliminate these symptoms.

Two other (rare) disorders, tardive dyskinesia and neuroleptic malignant syndrome (NMS), are also associated with antipsychotic drug use. Patients with NMS have high temperatures, rigid muscles, an altered mental state, and symptoms such as excessive sweating and irregular blood pressure or heart rhythm. Patients with NMS usually respond to treatment. Patients with tardive dyskinesia have involuntary movement of muscles in the chest, arms, and legs, or in the muscles in and around the face (including the tongue). Tardive dyskinesia may be irreversible.

Aprepitant

Side effects of aprepitant include fatigue, dizziness, stomach pain, nausea, hiccups, diarrhea, constipation, and loss of appetite. More serious, but less common, side effects have been reported, including hives, skin rash, difficulty breathing or swallowing, hoarseness, and swelling in the face, throat, tongue, lips, eyes, feet, ankles, or lower legs. If any of these more serious side effects occur, the patient should contact the treating physician immediately.

Serotonin Receptor Antagonists

Side effects include rashes, increased sweating, problems with taste or vision, flushing, agitation, sleep disorder, depersonalization, headache, fatigue, nausea, weakness, abdominal pain, constipation, diarrhea, hypertension, dizziness, chills and shivering, and dry mouth. Patients may also have abnormal liver function tests.

Dronabinol

Possible side effects are fatigue, weakness, abdominal pain, nausea, vomiting, heart palpitations, fast heart rate, facial flushing, amnesia, anxiety, an abnormal mental state, depersonalization, confusion, dizziness, and euphoria.

There are certain additional precautions and side effects associated with each of these drugs. Patients should be sure to notify their physician of any health concerns (including pregnancy) or medications they are taking. Patients should also ask about potential side effects for each individual medication before receiving any of these drugs.

Interactions

Promethazine

Promethazine interacts with central nervous system depressants, like alcohol and barbiturates. Therefore, the physician should be alerted to any medications the patient is taking, and doses of the drugs should be adjusted accordingly. Alcohol should be avoided. It has not been proven, but promethazine may interfere with the action of epinephrine.

Prochlorperazine

Like promethazine, prochlorperazine should be used cautiously, or not at all, with central nervous system depressants like alcohol and barbiturates. Prochlorperazine has also been shown to interact with anticonvulsant medication, guanethidene, propanolol, thiazide diuretics, and oral anticoagulants (like warfarin and coumadin).

Aprepitant

A physician can check the long list of possible drug interactions, which include possible effects on the action of certain chemotherapy drugs. Aprepitant also may interact with the blood thinner warfarin (Coumadin) and other popular drugs. The treating physician or pharmacist will need a complete list of other drugs the patient is taking before prescribing this antiemetic.

Serotonin Receptor Antagonists

These drugs may have very negative effects on the patient when combined with diuretics, anti-arrhythmia drugs, or high doses of anthracycline.

Dronabinol

Dronabinol interacts with the antiemetic prochlorperazine synergistically. Therefore, the use of these two drugs in combination results in a greater antiemetic effect. Patients taking central nervous system depressants, such as barbiturates or alcohol should notify their physician before taking marinol, since marinol may increase their effect. Although no drugs have been shown to interact with marinol, many drugs similar to marinol do interact with a number of other drugs, including central nervous system depressants such as alcohol or barbiturates, or drugs like flouxetine or disulfiram. Again, the physician should be alerted to any medications the patient is taking before beginning a course of dronabinol.

Antihypertensive

2008-08-12T22:01:00.001-07:00

Antihypertensives are a class of drugs that are used in medicine and pharmacology to treat hypertension (high blood pressure). There are many classes of antihypertensives, which—by varying means—act by lowering blood pressure. Evidence suggests that reduction of the blood pressure by 5-6 mmHg can decrease the risk of stroke by 40%, of coronary heart disease by 15-20%, and reduces the likelihood of dementia, heart failure, and mortality from cardiovascular disease.

Which type of medication to use initially for hypertension has been the subject of several large studies and resulting national guidelines.The fundamental goal of treatment should be the prevention of the important "endpoints" of hypertension such as heart attack, stroke and heart failure. Several classes of medications are effective in reducing blood pressure. However, these classes differ in side effect profiles, ability to prevent endpoints, and cost. The choice of more expensive agents, where cheaper ones would be equally effective, may have negative impacts on national healthcare budgets.^[1]

In the United States, the JNC7 (The Seventh Report of the Joint National Committee on Prevention of Detection, Evaluation and Treatment of High Blood Pressure) recommends starting with a thiazide diuretic if single therapy is being initiated and another medication is not indicated.^[2] This is based on a slightly better outcome for chlortalidone in the ALLHAT study versus other anti-hypertensives and because thiazide diuretics are relatively cheap.^[3] A subsequent smaller study (ANBP2) published after the JNC7 did not show this small difference in outcome and actually showed a slightly better outcome for ACE-inhibitors in older male patients.^[4]

Despite thiazides being cheap, effective, and recommended as the best first-line drug for hypertension by many experts, they are not prescribed as often as some newer drugs. Arguably, this is because they are off-patent and thus rarely promoted by the drug industry.^[5]

In the United Kingdom, the June 2006 "Hypertension: management of hypertension in adults in primary care"^[6] guideline of the National Institute for Health and Clinical Excellence, downgraded the role of beta-blockers due to their risk of provoking type 2 diabetes.^[7]

Available drugs

Diuretics

Hydrochlorothiazide, a popular thiazide diuretic

Diuretics help the kidneys eliminate excess salt and water from the body's tissues and blood.

Loop diuretics:
Thiazide diuretics:
- chlortalidone
- epitizide
- hydrochlorothiazide and chlorothiazide
- bendroflumethiazide
Thiazide-like diuretics:
Potassium-sparing diuretics:

Only the thiazide and thiazide-like diuretics have good evidence of beneficial effects on important endpoints of hypertension, and hence, should usually be the 1st choice when selecting a diuretic to treat hypertension. The reason why thiazides-type diuretics are better than the others is (at least in part) thought to be because of their vasodilating properties.^{[citation needed]}

Although the diuretic effect of thiazides may be apparent shortly after administration, it takes longer (weeks of treatment) for the full anti-hypertensive effect to develop.

Adrenergic receptor antagonists

Propranolol, the first beta-blocker to be successfully developed

Beta blockers (no longer 1st line therapy in many countries - see Lancet October 29th 2005):
Alpha blockers:
Mixed Alpha + Beta blockers:
- bucindolol
- carvedilol
- labetalol

Although beta blockers lower blood pressure, they do not have as positive a benefit on endpoints as some other antihypertensives.^[8] In particular, atenolol seems to be less useful in hypertension than several other agents.^[9] However, beta blockers have an important role in the prevention of heart attack in people who have already had a heart attack.^[10]

Despite lowering blood pressure, alpha blockers have significantly poorer endpoint outcomes than other antihypertensives, and are no longer recommended as a first-line choice in the treatment of hypertension.^[11] However, they may be useful for some men with symptoms of prostate disease.

Adrenergic receptor agonist

Alpha-2 agonists:
- clonidine
- methyldopa

Calcium channel blockers

Calcium channel blockers block the entry of calcium into muscle cells in artery walls.

dihydropyridines:
- amlodipine
- felodipine
- isradipine
- lercanidipine
- nifedipine(Adalat®)
- nimodipine
- nitrendipine
non-dihydropyridines:
- diltiazem
- verapamil

ACE inhibitors

Captopril, the prototypical ACE inhibitor

ACE inhibitors inhibit the activity of Angiotensin-converting enzyme (ACE), an enzyme responsible for the conversion of angiotensin I into angiotensin II, a potent vasoconstrictor.

Angiotensin II receptor antagonists

Valsartan, an angiotensin II receptor antagonist

Angiotensin II receptor antagonists work by antagonizing the activation of angiotensin receptors.

Aldosterone antagonists

Aldosterone receptor antagonists:

Aldosterone antagonists are not recommended as first-line agents for blood pressure,^[2] but spironolactone and eplerenone are both used in the treatment of heart failure.

Vasodilators

Vasodilators act directly on arteries to relax their walls so blood can move more easily through them; they are only used in medical emergencies.

sodium nitroprusside

Centrally acting adrenergic drugs

Central alpha agonists lower blood pressure by stimulating alpha-receptors in the brain which open peripheral arteries easing blood flow. Central alpha agonists, such as clonidine, are usually prescribed when all other anti-hypertensive medications have failed. For treating hypertension, these drugs are usually administered in combination with a diuretic.

Adverse effects of this class of drugs include sedation, drying of the nasal mucosa and rebound hypertension.

Some adrenergic neuron blockers are used for the most resistant forms of hypertension:

Choice

The choice between the drugs is to a large degree determined by the characteristics of the patient being prescribed for, the drugs' side-effects, and cost. For example, asthmatics have been reported to have worsening symptoms when using beta blockers. Most drugs have other uses; sometimes the presence of other symptoms can warrant the use of one particular antihypertensive (such as beta blockers in case of tremor and nervousness, and alpha blockers in case of benign prostatic hyperplasia). The JNC 7 report outlines compelling reasons to choose one drug over the others for certain individual patients.^[2]

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Antibiotic

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Contents

[edit] History of antibiotics

[edit] Antimicrobial pharmacodynamics

[edit] Administration

[edit] Antibiotic classes

[edit] Production

[edit] Side effects

[edit] Drug-Drug interactions

[edit] Contraceptive pill

[edit] Alcohol

[edit] Antibiotic resistance

[edit] Antibiotic misuse

[edit] Resistance modifying agents

[edit] Beyond antibiotics

[edit] References

[edit] External links

[edit] Resources

Antibiotics

HIV

Injection Drug Use and Hiv Infection

vitamin

dysmenorrhea

Risk factors

Primary Dysmenorrhea

Pathophysiology

Clinical Features

Treatment

Alternative treatments

Secondary Dysmenorrhea

Pathophysiology

Clinical Features

Treatment

Related Problems

diarrheA

anti- depressant

paracetamol

seizures

antiepileptic

pharmacy

low back pain

antiemetic

Antihypertensive

Available drugs

Diuretics

Adrenergic receptor antagonists

Adrenergic receptor agonist

Calcium channel blockers

ACE inhibitors

Angiotensin II receptor antagonists

Aldosterone antagonists

Vasodilators

Centrally acting adrenergic drugs

Choice