Self-administration of any drug in a culturally disapproved manner that causes adverse consequences.

A behavioral pattern of drug abuse characterized by overwhelming involvement with the use of a drug (compulsive use), the securing of its supply and a high tendency to relapse after discontinuation.

The physiological state of neuroadaptation produced by repeated administration of a drug, necessitating continued administration to prevent the appearance of the withdrawal syndrome.

The exaggerated expression of the original condition sometimes experienced by patients immediately after cessation of an effective treatment.

The reoccurrence on discontinuation of an effective medical treatment of the original condition from which the patient suffered.

Tolerance has developed when after repeated administration, a given dose of a drug produces decreased effect, or conversely, when increasingly larger doses must be administered to obtain the effects observed with the original use.

The psychologic and physiologic reactions to abrupt cessation of a dependence-producing drug.