Co-Occurring Disorders: Symptoms, Risk Factors, and Treatment

Medically Reviewed By

Dr. Po-Chang Hsu

Dr. Po-Chang Hsu

On April 14, 2024

Written By

Amanda Stevens

Amanda Stevens, B.S.

On November 18, 2023

What you will learn

  • A co-occurring disorder is the presence of a mental health condition and substance use that occur together.
  • These disorders may occur independently but simultaneously, or they may arise from one worsening the other.
  • There are many possible risk factors for developing co-occurring disorders, including genetic and environmental factors.
  • Treatment for co-occurring disorders requires an integrative approach that addresses both conditions concurrently.
Reading Time: 4 minutes

Millions of people struggle with mental health conditions and substance use disorders, often together, which are known as co-occurring disorders. These conditions can occur independently or may influence each other.

About 21.5 million American adults have a co-occurring mental illness and substance use disorder in 2022.[1] Together, these conditions can intensify symptoms and risks and create challenges in treating both successfully.

What Are Co-Occurring Disorders?

Co-occurring disorders occur when someone has a mental health condition and a substance use disorder that occur simultaneously.[2] Though this term usually applies to these two groups of disorders, it can also apply to other behavioral health conditions like a mental disorder and an intellectual disability.

When a mental health condition and substance use disorder co-occur, they can differ in severity or change over time. People with co-occurring disorders may experience more significant symptoms and challenges with treatment.

What Are Examples of Co-Occurring Disorders?

Some conditions commonly co-occur, such as anxiety or depression with substance use. Attention deficit/hyperactivity disorder (ADHD), schizophrenia, and some personality disorders are also more likely to co-occur with substance use disorders.

The substances can vary but may include:

  • Tobacco
  • Alcohol
  • Opioids
  • Marijuana
  • Stimulants
  • Hallucinogens
  • Prescription medications

What Mental Health Conditions Are Common with Co-Occurring Disorders?

There are a range of mental health conditions that can co-occur with substance use disorder, including anxiety disorders like generalized anxiety disorder and depressive disorders like clinical depression.

Co-occurring disorders aren’t limited to these groups of conditions, however. ADHD, which is characterized by impulse control issues, poor focus and attention, and hyperactivity, is a commonly co-occurring disorder.

PTSD and other trauma disorders are also common, which may include nightmares, flashbacks, depression, anxiety, and in some cases, substance use. Conduct disorders may present with co-occurring disorders, as they align with some of the behaviors of substance use, such as deceitful behavior, destructive behavior, issues with authority, and engaging in illegal activities.

Some process disorders, also known as process addictions, may co-occur with substance use. These may include internet addiction, video game use disorder, sex addiction, gambling addiction, or eating disorders. Addiction interaction disorder, characterized by alternating or simultaneous addictions, often includes substance use disorders among other types of behavioral addictions.

Who Is at the Greatest Risk of Developing a Co-Occurring Disorder?

Roughly 21.5 million Americans have a co-occurring mental health condition and substance use disorder. Over half of these people are men, indicating it may be more common in men than women.[3] People who struggle with anxiety and depression also have a higher risk of co-occurring substance use disorders.

Some people have genetic risk factors that contribute to mental health conditions, substance use disorders, or both, but the environment can also play a role. For example, alcohol use disorder is associated with conditions like anxiety and depressive disorder. Chronic stress, trauma, peer drug use, family strife, and social acceptance of substance use can also contribute to these conditions.

With co-occurring disorders, one may influence the other and exacerbate both symptoms. Substance use may lead to the development of a mental health condition like depression, but it could also worsen an existing disorder. In some cases, a person with a mental health condition may turn to drugs or alcohol to self-medicate symptoms. For example, a person with post-traumatic stress disorder (PTSD) drinks alcohol to relax, which turns into an addiction.

What Are the Symptoms of Co-Occurring Disorders?

Co-occurring disorders show symptoms related to the specific mental health condition or substance use disorder. The symptoms are often specific to the substance used, but may include:

  • Seeking substances despite consequences
  • Devoting excessive time to getting the substance
  • Intense cravings
  • Tolerance
  • Withdrawal
  • Neglecting regular activities
  • Expressing a desire to stop but unable to

People with co-occurring disorders experience an increased risk for devastating effects like social isolation, relapses, problems with interpersonal relationships, legal troubles, victimization, and serious medical conditions.

How Do Co-Occurring Disorders Affect Addiction?

The relationship between substance use disorder and mental health can be complex and involve overlapping risk factors.

Genetics are a big contributor to substance use disorder and mental health disorders. Specific genes can be a risk factor for developing a substance use disorder and affect how an individual responds to different substances.

Certain mental illnesses increase the risk of substance use disorders as individuals seek to control their symptoms, such as anxiety. This may relieve symptoms temporarily, but over time, it will worsen both the mental health condition and the substance use.

Substance use and a disorder that arises from it can lead to a mental health disorder. Ongoing substance use leads to changes in the brain, and the longer a substance is used, the greater those changes become long-term. As a result, these people may develop a mental health condition.

How Are Co-Occurring Disorders Treated?

In the past, co-occurring disorders were addressed with separate consecutive treatments. It was believed that one disorder must be treated before the other, which neglected the role and influence two disorders have over one another.

Now, co-occurring disorders are treated with an integrated approach that coordinates mental health and substance abuse interventions.[4] This often includes types of behavioral therapy, such as cognitive behavioral therapy (CBT) or dialectical behavior therapy (DBT), to improve negative behaviors and identify the underlying causes of substance use.

In addition, treatment for co-occurring disorders may include a variety of therapeutic modalities that are often used with either substance use disorder or mental health conditions, such as medication, psychotherapy (talk therapy), experiential therapy, relapse prevention, and group therapy.

The overarching goal of co-occurring disorder treatment is to help the person address their experiences and how their conditions overlap. This is more effective than treating conditions on their own.

If you are wondering what CBT or DBT services are available near you, we offer dialectical behavior therapy and cognitive behavioral therapy in NYC.


Frequently Asked Questions

How Common Are Co-Occurring Disorders?

People with mental health disorders are more likely to struggle with a substance use disorder than those without. Research suggests a significant overlap, but estimates vary; it’s important to note that not all individuals with a mental illness or substance use disorder will develop co-occurring disorders.

Does Substance Use or Mental Illness Come First?

There are many ways that co-occurring disorders may develop. In some cases, co-occurring disorders exist independently of each other, but someone with a mental health condition may self-medicate with drugs or alcohol to relieve symptoms like anxiety or depression, leading to tolerance and addiction over time.

Conversely, regular substance use can create anxiety or depression. These individuals are at a higher risk for other problems because of substance, such as sexual victimization, which can also indirectly lead to mental health conditions like anxiety or PTSD.

What’s the Difference Between Co-Occurring Disorders and Dual Diagnosis?

Co-occurring disorder is a more recent term for dual diagnosis, but they both refer to mental health and substance use disorders that occur together. Other terms for these conditions may include concurrent disorders, dual disorder, or co-morbidity, though the latter is often used to refer to diseases outside of mental health.

What Is the First Step in Treating Co-Occurring Disorders?

Because the symptoms of certain mental health conditions can mimic those of substance use disorders, it’s important that both disorders are correctly diagnosed with a careful assessment. This is often challenging and requires an experienced mental health professional with a keen understanding of both mental illness and substance abuse. 

Begin Healing: Tackle Your Co-Occurring Disorders Now

Co-occurring disorders can be more challenging for the people struggling with them, but they’re highly treatable. If you or a loved one has co-occurring disorders, it’s important to seek help from a qualified treatment center that offers personalized integrative therapies that address the symptoms of each condition and how they affect one another.

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[1] SAMHSA. (2024, March 29). Co-Occurring Disorders and Other Health Conditions.

[2] U.S. Department of Health and Human Services. (n.d.). Substance use and co-occurring mental disorders. National Institute of Mental Health. Retrieved from on May 1, 2023.

[3] Working with specific populations of men in Behavioral Health Settings. (n.d.). Retrieved  from on May 2, 2023.

[4] Dual diagnosis: Mental illness and substance abuse – dartmouth. (n.d.). Retrieved from on May 2, 2023.