Not using drugs or alcohol.
Abstinence refers to the avoidance of drugs or alcohol. Some treatment programmes aim to help a person stop using alcohol and other drugs entirely. The term is also used in the drug education and prevention field and refers to the aim of trying to stop young people from ever using drugs (DrugWise).
Refraining from drug use or (particularly) from drinking alcoholic beverages, whether as a matter of principle or for other reasons. Those who practise abstinence from alcohol are termed "abstainers", "total abstainers", or-in a more old-fashioned formulation-"teetotallers". The term "current abstainer", often used in population surveys, is usually defined as a person who has not drunk an alcoholic beverage in the preceding 12 months; this definition does not necessarily coincide with a respondent's self-description as an abstainer. The term "abstinence" should not be confused with "abstinence syndrome", an older term for withdrawal syndrome. See also: temperance (WHO Lexicon of alcohol and drug terms)
NIDA glossary