Not using drugs or alcohol.
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