For other uses, see Drug (disambiguation).
Missing image
Many drugs are provided in tablet form.

A drug is any substance that can be used to modify a chemical process or processes in the body, for example to treat an illness, relieve a symptom, enhance a performance or ability, or to alter states of mind. The word "drug" is etymologically derived from the Dutch/Low German word "droog", which means "dry", since in the past, most drugs were dried plant parts.



The term "drug" is necessarily a vague one, being defined by intent: for example, foods consumed for normal metabolism are not generally considered "drugs", but the same foods consumed for a more specific purpose (such as the use of alcohol as a depressant or caffeine as a stimulant) may be. Depending on the definition used, the same substance may even be considered both a food and a drug at the same time. The term "medication" is frequently applied to drugs used for medical treatment, presumably to avoid confusion with recreational drugs.


The effects of a particular drug can vary greatly depending on a number of factors:

  • dosage
  • combination with other drugs or foods
  • means of intake (ingestion, inhalation, injection, absorption)
  • the personal condition and circumstances of the subject (user or patient)
  • the user's expectations or beliefs about the drug (placebo effect)


All drug use includes a certain set of risks which must be weighed over the benefits. Along with the potential to treat illness and improve quality of life, they also have side effects which may include dependence, addiction, psychological disorders, physical deterioration or even death. Before taking any drug, one should be well aware of all the risks and side effects. For some drugs such as cannabis, their legal status poses more risk than use of the drug itself, as simple possession alone may lead to imprisonment. Others such as alcohol, caffeine and chocolate are so integrated into society that we forget that they are even drugs at all.


Two patterns of distribution, licensed and illegal, are created by laws designed to prevent or punish perceived abuse or to protect the interests of licensed producers, suppliers and users. Laws may be designed also (not least with respect to alcohol and tobacco) to generate government tax revenue. Legislation tends however to limit our ideas about which substnaces should qualify as drugs. Broader ideas (which might include tea, coffee and saffron) allow perception of other patterns of distribution.


Main article: Medication

In the United States, medical professionals may obtain drugs from drug companies or pharmacies (which in turn purchase drugs from the drug companies). Pharmacies may also supply a drug directly to patients, authorized by a prescription from a medical professional, if the drug can be safely self-administered. Most drugs are relatively high-cost for patients to purchase directly when first distributed, although health insurance may mitigate some of the cost. When the patent for a drug runs out, a generic drug (some known as simply a "generic") is usually synthesized and released by competing companies, causing the price to drop markedly. Drugs which don't require prescription by a medical professional are known as over-the-counter (OTC) drugs and can be sold in stores without pharmacy association.


Main article: Prohibition (drugs)

Illegal drug use is often termed recreational, but recreational drug use can be quite legal. Recreational use of alcohol, for example, is quite legal in many states and countries. Also, illegal users may claim that their use is medicinal or therapeutic: medical necessity has been used successfully in England as a defence against charges of illegal possession of cannabis.

The quality of a drug supplied illegally can be very unreliable.

See Drug policy of the Netherlands.

Drug addiction

Main article: Drug addiction

Drug addiction, or substance dependence is the compulsive use of drugs, to the point where the user has no effective choice but to continue use. This phenomenon has occurred to some degree throughout recorded history (see "opium"), though modern agricultural practices, improvements in access to drugs, and advancements in biochemistry have exacerbated the problem significantly in the 20th century with the introduction of purified forms of active biological agents, and with the synthesis of hitherto unknown substances, such as methamphetamine and gamma-hydroxybutyrate (GHB). While "addiction" has been replaced by "dependency" as a clinical term, the terms are used interchangeably here.


Drugs may be classified in many different ways, according to mechanism of action, effects, or even legal status.


Usage of most of drugs is regulated to some extent. While details vary with location, these are somewhat usual regulations in the Western world:

Not regulated:

Regulated to some extent (age or labeling requirements, for example) but available over the counter:

Prescription drugs, prohibited for non-medical use:

Varies from tolerated to prohibited for medical use:

Varies from prohibited for non-medical use to prohibited for any use

Prohibited for any use, no medical uses currently allowed

UN documents

Three international UN treaties regulate drugs laws:

The UN Office on Drugs and Crime (http://www.unodc.org/) is charged with overseeing these treaties and maintains a list of signatory nations at http://www.unodc.org/unodc/treaty_adherence.html.

See also

External links


  • United Nations Drug Control (http://www.tni.org/drugsungass-docs/uncontrol.htm) A critical review of the United Nations drug control system (Transnational Institute)
  • Dutch Jellinek clinic (http://www.jellinek.nl/brain/index.html) Shows the micro biological effect of several kinds of drugs on brain cells, using flash animations.
  • The Vaults of Erowid (http://www.erowid.org) Reliable, non-judgmental information about psychoactive plants and chemicals and related issues. Working with academic, medical, and experiential experts to develop and publish new resources.
  • The Lycaeum (http://www.lycaeum.org) An extensive resource for information on psychoactive plants and chemicals including first-person reports of experiences as well as a discussion forum.
  • Dopers.org (http://www.dopers.org) Numerous links to sites espousing harm-reduction, drug-law reform, cognitive liberties, and drug knowledge.
  • PiHKAL: A Chemical Love Story (1988) ISBN 0963009605
  • TiHKAL: The Continuation (1991) ISBN 0963009699
  • The Pursuit of Oblivion: A Global History of Narcotics (2002) ISBN 0393051897
  • Forces of Habit: Drugs and the Making of the Modern World (2002) ISBN 0674010035
  • Pharmako/Dynamis: Stimulating Plants, Potions and Herbcraft (2002) ISBN 1562791257
  • Illegal Drugs: A Complete Guide to Their History, Chemistry, Use and Abuse (2001) ISBN 0970313012
  • The Encyclopedia of Psychoactive Substances (2000) ISBN 0312263171
  • A Brief History of Drugs: From the Stone Age to the Stoned Age (1999) ISBN 0892818263
  • Phantastica: A Classic Survey on the Use and Abuse of Mind-Altering Plants (1998) ISBN 0892817836
  • Essential Substances: A Cultural History of Intoxicants in Society (1995) ISBN 1568360754
  • Pharmako/Poeia: Plants Powers, Poisons, and Herbcraft (1995) ISBN 1562790692
  • Plant Intoxicants: A Classic Text on the Use of Mind-Altering Plants (1994) ISBN 0892814985
  • The alchemy of culture: Intoxicants in society (1993) ISBN 0714117366ca:droga

da:Lægemiddel de:Arzneimittel es:Droga ko:마약 id:Obat it:Droga nl:Drug pl:Narkotyk pt:Droga sv:Drog ms:Dadah


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