Common term for sulfonamide drug, any member of a class of synthetic antibacterial drugs with a particular chemical structure including both sulfur and nitrogen atoms. Their effectiveness against bacteria was discovered in 1932 by Gerhard Domagk, and they became the first chemical substances systematically used against human bacterial infections. Sulfa drugs inhibit the growth and multiplication of certain bacteria (but do not kill them) by interfering with the synthesis of folic acid. Because of their toxicity and growing bacterial resistance, sulfa drugs are no longer in common use (except for urinary-tract infections, certain forms of malaria, and preventing infection of burns), having been largely superseded by less toxic antibiotics.
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Harmful effects of drugs, from overdose or sensitivity to regular doses. Many medicines are dangerous; the margin between dose and overdose is often narrow. A normally safe dose may be toxic in some people, over time, or in combination with certain foods, alcohol, or other drugs. Safeguards to prevent drug poisoning include testing in animals, then human volunteers, and then patients. Drugs unsafe for self-medication are available only to doctors or by prescription. Pharmacists advise the public on proper use.
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Physical and/or psychological dependency on a psychoactive (mind-altering) substance (e.g., alcohol, narcotics, nicotine), defined as continued use despite knowing that the substance causes harm. Physical dependency results when the body builds up a tolerance to a drug, needing increasing doses to achieve the desired effects and to prevent withdrawal symptoms. Psychological dependency may have more to do with one's psychological makeup; some people may have a genetic tendency to addiction. The most common addictions are to alcohol (see alcoholism), barbiturates, tranquilizers, and amphetamines, as well as to the stimulants nicotine and caffeine. Initial treatment (detoxification) should be conducted with medical supervision. Individual and group psychotherapy are critical elements. Alcoholics Anonymous and similar support groups can increase the success rate of other efforts. The ability to admit addiction and the will to change are necessary first steps.
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Any chemical agent that affects the function of living things. Some, including antibiotics, stimulants, tranquilizers, antidepressants, analgesics, narcotics, and hormones, have generalized effects. Others, including laxatives, heart stimulants, anticoagulants, diuretics, and antihistamines, act on specific systems. Vaccines are sometimes considered drugs. Drugs may protect against attacking organisms (by killing them, stopping them from reproducing, or blocking their effects on the host), substitute for a missing or defective substance in the body, or interrupt an abnormal process. A drug must bind with receptors in or on cells and cannot work if the receptors are absent or its configuration does not fit theirs. Drugs may be given by mouth, by injection, by inhalation, rectally, or through the skin. The oldest existing catalogue of drugs is a stone tablet from ancient Babylonia (circa 1700 BC); the modern drug era began when antibiotics were discovered in 1928. Synthetic versions of natural drugs led to design of drugs based on chemical structure. Drugs must be not only effective but safe; side effects can range from minor to dangerous (see drug poisoning). Many illegal drugs also have medical uses (see cocaine; heroin; drug addiction). Seealso drug resistance; pharmacology; pharmacy.
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Synthetic version of a controlled narcotic substance. Designer drugs usually are synthesized for the first time in an attempt to create a chemical whose molecular structure differs only slightly from that of some well-known controlled substance but whose effects are essentially the same. Because of the difference in molecular structure, the designer drug, unlike the controlled substance, ordinarily will not be specifically listed as illicit by law-enforcement organizations. Many designer drugs are manufactured in clandestine laboratories, often by amateurs; for this reason they are sometimes more dangerous than the drugs they are intended to replace. One of the best-known is MDMA (3,4- methylenedioxymethamphetamine), a variation of methamphetamine, popularly called Ecstasy. Nonnarcotic synthetic chemical compounds designed to interact with specific proteins and enzymes in order to combat disease also have been called designer drugs.
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Agency of the U.S. Department of Health and Human Services. Established in 1927, it inspects, tests, approves, and sets safety standards for foods and food additives, drugs, chemicals, cosmetics, and household and medical devices. It can prevent untested products from being sold and take legal action to halt the sale of undoubtedly harmful products or of products that involve a health or safety risk. Its authority is limited to interstate commerce; it cannot control prices nor directly regulate advertising except of prescription drugs and medical devices.
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Medication, also referred to as medicine, can be loosely defined as any substance intended for use in the diagnosis, cure, mitigation, treatment, or prevention of disease. Other synonyms include pharmacotherapy, pharmacotherapeutics, and drug treatment.
Types of medicines:
hypnotic, anaesthetics, antipsychotic, antidepressant (including tricyclic antidepressants, monoamine oxidase inhibitor, lithium salt, selective serotonin reuptake inhibitor), anti-emetic, anticonvulsant and antiepileptic, anxiolytic, barbiturate, movement disorder drug, stimulant (including amphetamines), benzodiazepine, cyclopyrrolone, dopamine antagonist, antihistamine, cholinergic, anticholinergic, emetic, cannabinoids, 5-HT antagonist
Euthanasia is not permitted by law in many countries, and consequently medicines will not be licenesed for this use in those countries.
The International Narcotics Control Board of the United Nations imposes a world law of prohibition of certain medications. They publish a lengthy list of chemicals and plants whose trade and consumption (where applicable) is forbidden. OTC medications are sold without restriction as they are considered safe enough that most people will not hurt themselves accidentally by taking it as instructed. Many countries, such as the United Kingdom have a third category of pharmacy medicines which can only be sold in registered pharmacies, by or under the supervision of a pharmacist.
For patented medications, countries may have certain mandatory licensing programs which compel, in certain situations, a medication's owner to contract with other agents to manufacture the drug. Such programs may deal with the contingency of a lack of medication in the event of a serious epidemic of disease, or may be part of efforts to ensure that disease treating drugs, such as AIDS drugs, are available to countries which cannot afford the drug owner's price.
Zoopharmacognosy: Animal usage of drugs and non-foods.
A recent report from Urch Publishing estimated that about one third of the pharma market by value is accounted for by blockbusters. About 100 products are blockbusters. The top seller was Lipitor, a cholesterol-lowering medication marketed by Pfizer with sales of $12.2 billion.
|Medication||Trade name||Company||Sales (billion $), year|
|atorvastatin||Lipitor||Pfizer||12 (2007) <|
|clopidogrel||Plavix||Bristol-Myers Squibb and sanofi-aventis||5.9 (2005)|
|enoxaparin||Lovenox or Clexane||sanofi-aventis|
|budesonide||Pulmicort/Rhinocort||AstraZeneca||1.3 (2003) (plus some fraction of the $0.6bn sales of Symbicort)|