An Introduction to Co-Occurring Disorders

Prevalence of Co-Occurring Disorders

Over 2.3 million adolescents (aged 12-17) and 7.7 million young adults (aged 18-25) used illegal drugs or misused prescription medication in the U.S. in 2014. About 2.9 million adolescents and 20.8 million young adults — more than half of the young adult population — consumed alcohol in the past month.

Mental health disorders are a subject of increasing concern for young adults. One in five adolescents has a mental health disorder. The most common are anxiety disorders, depression and attention-deficit hyperactivity disorder (ADHD). Young people may also struggle with bipolar disorder, schizophrenia and borderline personality disorder.

Risks Factors

Mental health disorders and substance use are tightly linked. Often, when a mental health disorder goes undiagnosed or untreated, a young person will attempt to self-medicate or self-treat with drugs or alcohol. Studies show that ADHD, anxiety disorders, post-traumatic stress disorder and depression all increase risk of drug use and dependence in adolescents.

At the same time, substance use poses a serious risk for developing a mental health disorder. Heavy marijuana use is a demonstrated risk factor for triggering episodes of psychosis, particularly in those with a family history of psychotic disorders. Misuse of prescription medications like stimulants or certain antidepressants can lead to manic or unusually irritable mood states.

Happily, research also shows that identifying and treating mental health disorders can reduce substance use. Similarly, reducing substance use can improve treatment outcomes for mental health disorders.