Alex Ehsan, MD, PhD ยท Medical search

Dual Diagnosis

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

What is dual diagnosis?

If you have a dual diagnosis, that means that you have both a mental disorder and a substance use disorder (SUD), either with alcohol or drugs. A dual diagnosis is a type of comorbidity, which is when someone has two disorders at the same time. Another name for this is co-occurring disorders.

Mental and substance use disorders often occur together. Many people who develop SUDs are also diagnosed with mental disorders. And the reverse is true; many people with mental disorders will develop an SUD. Having both types of disorders is even more common in teenagers, people with serious mental illness, and people with certain mental disorders.

Why do substance use disorders and mental disorders occur together?

Although these problems often occur together, this does not mean that one caused the other, even if one appeared first. In fact, it can be hard to figure out which came first. Researchers think that there are three possible reasons as to why they often occur together:

What are the treatments for dual diagnosis?

If you have a dual diagnosis, it is usually better to treat both conditions at the same time rather than separately. You and your health care provider can work on a treatment plan that fits your needs.The plan should take into account your age, which substance(s) you are misusing, and which specific mental disorder(s) you have. The plan may include:

NIH: National Institute on Drug Abuse

Questions for your care team

General prompts to help prepare for your appointment.

For a life-threatening emergency, call 911 in the U.S. or your local emergency number.

Browse all patient guides