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Drug abuse is the use of illegal drugs, or the misuse of prescription or over-the-counter drugs, for at least a year with negative consequences. Drug abuse can lead to drug dependence or addiction.

  • Drug dependence: a person needs a drug to function normally. Abruptly stopping the drug leads to withdrawal symptoms.
  • Drug addiction: compulsive use of a substance, despite its negative or dangerous effects.

Drugs of abuse include opiates (opium, methadone), cannabis, amphetamine, ecstasy and cocaine. See also Controlled drugs

Substance (mis)use Medline Plus Encyclopaedia

Drug abusers may present with a variety of dependence-related medical conditions. Seen in primary care, they may admit their dependence or may attempt to obtain drugs by deception.

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