Drugs and Mental Illness

Findings on the Link Between Mental Health and Substance Use Disorders


According to the National Institute on Drug Abuse, mental illness and substance use disorder commonly occur together. Referred to as comorbidities, individuals with diagnosable mental health disorders frequently experience substance use disorders (SUD). The problem is widespread with as many of half of those with mental illness experiencing a substance use disorder within their lifetime.

Common mental health disorders experienced by people with substance use disorders:

  • Generalized anxiety disorder
  • Panic disorder
  • Post-traumatic stress disorder (PTSD)
  • Depression
  • Bipolar disorder
  • Attention-deficit hyperactivity disorder (ADHD)
  • Psychotic illness
  • Borderline personality disorder
  • Antisocial personality disorder
  • Schizophrenia

Major depression, schizophrenia, and bipolar disorder are all considered serious mental illnesses (SMI). SMI is also associated with any mental disorder that “causes serious impairment.” As noted by the National Institute on Drug Abuse, approximately “1 in 4 individuals with SMI also have a SUD.”

It is not known why there is a connection between mental illness and drug or alcohol abuse, but both mental health disorders and substance use disorders are treatable. It is important to seek a diagnosis early. 

Youth and Comorbidity

Adults are not the only ones to experience comorbidities. Youth also experience comorbid disorders including alcohol and drug addiction while they are also suffering from a mental health disorder.

Drug and alcohol use during youth can have a detrimental impact on a developing brain. Studies show that drug use during youth can be a “strong risk factor” for adult substance use disorder and potentially a risk factor for mental health disorders later in life.

If you believe that your child is experiencing a mental health crisis or has a drug or alcohol addiction, it is important to seek professional help. Addressing mental health and substance use disorders early is the best way to help a child.