GlossaryCo-Occurring DisordersMental Health

What Is Dual Diagnosis? Co-Occurring Disorders Explained

Dual Diagnosis (Co-Occurring Disorders)

Definition

Dual diagnosis, also called co-occurring disorders, is when a person has both a mental health disorder and a substance use disorder at the same time. The two conditions can influence each other, so the most effective care treats them together rather than separately.

If you are asking what is dual diagnosis or what is a co occurring disorder, the key idea is that mental health and substance use are deeply connected and benefit from integrated treatment. This page is informational only and is not medical advice; a qualified provider can assess an individual situation.

What Does Dual Diagnosis Mean?

A dual diagnosis means two conditions are present together—for example, depression and alcohol use disorder, or anxiety and opioid use disorder. According to the U.S. Substance Abuse and Mental Health Services Administration (SAMHSA), having two or more disorders can complicate diagnosis and treatment, which is why a coordinated approach matters. You can read SAMHSA’s overview of managing life with co-occurring disorders.

Why Do Mental Health and Substance Use Often Occur Together?

There is no single cause, but several factors help explain the overlap:

  • Self-medication: some people use substances to cope with symptoms such as anxiety, depression, or trauma, which can deepen both conditions over time.
  • Shared risk factors: genetics, chronic stress, and adverse experiences can raise the risk of both disorders.
  • Brain effects: substance use can change brain chemistry in ways that worsen or trigger mental health symptoms, and vice versa.

Because the conditions feed into one another, treating only one often leaves the other to undermine recovery.

What Is Integrated Treatment for Co-Occurring Disorders?

Integrated treatment addresses mental health and substance use in the same coordinated plan, often within the same sessions, rather than sending a person to separate, disconnected programs. SAMHSA identifies integrated care as a best practice for co-occurring disorders. Common elements include:

How Does DMHBH Treat Dual Diagnosis?

DMHBH provides outpatient, integrated care for co-occurring mental health and substance use disorders through our co-occurring disorders program and intensive outpatient program (IOP), serving DeSoto and Charlotte County, Florida.

Frequently Asked Questions About Dual Diagnosis

What is the difference between dual diagnosis and co-occurring disorders?

They mean the same thing: having a mental health disorder and a substance use disorder at the same time. “Co-occurring disorders” is the term used most often by clinicians and SAMHSA.

Which should be treated first, the mental health condition or the substance use?

Integrated care treats both together rather than one before the other, which research suggests leads to better outcomes than separate treatment.

How common is dual diagnosis?

Many adults experience both a mental illness and a substance use disorder. SAMHSA notes that co-occurring disorders are common and benefit from integrated treatment.

Can dual diagnosis be treated on an outpatient basis?

Yes. Many people receive effective integrated care through outpatient programs such as IOP while living at home, depending on their needs and safety.

Does DMHBH treat co-occurring disorders?

Yes. DMHBH offers integrated outpatient treatment for co-occurring mental health and substance use disorders, including IOP. We refer out for medical detox when needed and support recovery afterward.

Have Questions About Your Care?

Understanding the words behind treatment is a good first step. When you are ready to talk through your options, our team is here to help.