Drug addiction

Drug addiction, physical rather than psychological dependence upon an intoxicating substance, such that deprivation causes the addict to experience withdrawal. Common drugs that can produce addictions include alcohol, nicotine (in tobacco), caffeine, barbiturates, and opiates (opium, morphine, heroin). Not all who take dependence-producing drugs become dependent on them. Withdrawal from addictive drugs such as alcohol can itself be dangerous, and detoxification is often medically supervised.

See also: Drug; Narcotic.