Substance Use Disorders and Comorbid Mental Illness

Definition of Terms

Mental illness

An inclusive term for psychiatric disorders, typically characterized by an impairment of mood, behavior, and/or cognition.Substance use disorder

A collective term indicating a disorder associated with harmful use of a specific substance (e.g., alcohol, cannabis). The updated DSM-5 combines previous diagnoses of substance-specific abuse and dependence into a single diagnosis called “substance use disorder” (e.g., alcohol use disorder, cannabis use disorder).Mood disorders

A group of psychiatric disorders characterized by a pervasive disturbance of affect not due to any other physical or mental illness

Anxiety disorders

A group of psychiatric disorders characterized by excessive worry and fear that is often accompanied by both physical and mental symptoms.

A type of psychiatric disorder characterized by persistent low mood and a loss of interest or pleasure in activities normally enjoyed.

A type of psychiatric disorder characterized by episodes of mania or hypomania (elevated or irritable mood causing difficulties in daily life functioning), often followed by episodes of depression.

A type of psychiatric disorder characterized by consistent and excessive anxiety about life circumstances, often accompanied by additional symptoms such as restlessness, irritability, fatigue, and insomnia.

A type of psychiatric disorder characterized by persistent and unreasonable fear of social and performance situations in which the individual might be scrutinized and judged.Panic disorder

A type of psychiatric disorder characterized by short episodes of intense anxiety and autonomic system hyperactivity. Fear of avoiding situations in which previous attacks have occurred often results in agoraphobia.Substance-independent disorder

A psychiatric disorder that is not the result of intoxication or withdrawal of a drug or toxin.Substance-induced disorder

A psychiatric disorder that is the result of intoxication or withdrawal of a drug or toxin.