Narcotic drug addiction is a physical and psychological dependence on a specific class of drugs.
Narcotics are drugs that produce a change in response to sensations.
Narcotics also produce mood changes, unconsciousness, or deep sleep. Examples of narcotics are heroin, codeine, morphine, and methadone. A person addicted to a drug may have to withdraw from it because of shortage of supply, lack of money, or confinement in a controlled environment, such as jail, hospital, or other institution, in which the drug is not available. The person may also decide to stop taking the drug to break his or her drug habit. A narcotic addict is someone who has a history of frequent or chronic use of narcotics over an extended period.