Introduction​

Problem drinking

Problem drinking is not a DSM diagnosis but is commonly used to refer to alcohol consumption that is greater than low-risk drinking guidelines. Note that there are significant international variations in standard drink size and in the definition of risk.

Problem drinking involves potential social, physical or psychological consequences, but DSM criteria for a substance use disorder is not met.

Concurrent disorder

A concurrent disorder is a co-occurring psychiatric and substance use disorder. It is distinct from "dual diagnosis," which refers to the presence of both a psychiatric disorder and a developmental delay. In some countries, including the United States, dual diagnosis is the term used for a concurrent disorder. 

Intoxication and withdrawal

Intoxication and withdrawal are characterized by the development of a reversible substance-specific syndrome due to recent ingestion of or exposure to a substance (intoxication) or cessation of or reduction in use of a substance (withdrawal).

• Intoxication: Clinically significant maladaptive behavioural or psychological changes that are due to the effect of the substance on the central nervous system. These changes can include belligerence, mood lability, cognitive impairment, impaired judgment, impaired social or occupational functioning. The changes develop during or shortly after using the substance.
• Withdrawal: Clinically significant distress or impairment in social, occupational or other important areas of functioning due to the absence of the substance.

The symptoms are not due to a general medical condition and are not better accounted for by another mental disorder.

Tolerance

Tolerance refers to the need for greatly increased amounts of the substance to achieve intoxication (or the desired effect) or to a markedly diminished effect with continued use of the same amount of the substance.

Polysubstance dependence

Polysubstance dependence is diagnosed when a person uses three or more substances (with the exception of caffeine and tobacco) and meets criteria for dependence. No single substance accounts for the problems experienced by the patient.