Why Do Addiction and Mental Health Disorders Often Occur Together?

Updated on 4/13/23

Content reviewed by Karen Rubenstein, LMFT

Individuals who have substance use disorder (SUD) experience increased risks of developing other mental health disorders and vice versa. When mental health disorders and addiction are present in the same person, they are referred to as co-occurring disorders. If co-occurring disorders are not appropriately managed consistently, the two conditions can interact with one another and worsen the intensity of the symptoms of both conditions. This blog dives deeper into the reasons why addiction and mental health disorders often co-occur.

Nearly 7.7 million adults struggle with co-occurring SUD and at least one other mental health condition. Among the 20.3 million adults who struggle with SUD, nearly 40% also struggle with their mental health. Among the 42.1 million adults who struggle with their mental health, almost 19% also struggle with SUD.

Common Co-Occurring Disorders

There is no specific combination of substance use and mental health disorders that define co-occurring disorders. However, several mental health conditions commonly co-occur with SUD. Some of these include:

  • Depression
  • Anxiety disorders
  • Schizophrenia
  • Personality disorders
  • Mood disorders

It is essential to recognize the prevalence of these conditions. If a loved one is diagnosed with a specific health disorder, one can be aware of their vulnerability to developing SUD. Although these conditions commonly occur together, it does not always mean that one condition causes or follows the other.

Reasons Co-Occurring Disorders Are Common with Substance Use Disorder and Mental Health Disorders

Research has found that there are three possibilities, which could explain why co-occurring disorders are as prevalent as they are.

1. Both mental health conditions and substance use disorder (SUD) develop from the same risk factors

The first possibility of why these conditions occur together is that both mental health conditions and SUD develop from shared risk factors. These include genetic, environmental and circumstantial risk factors. Examples of risk factors include:

  • Genetic risk factors are any factors that may predispose an individual to develop a disorder. For example, having a relative with a mental health or SUD can make an individual more vulnerable to developing either or both conditions. Even when an individual does not have relatives who are diagnosed with a disorder, they may develop a mental health or SUD if they were born with gene sequencing that predisposes them to SUD or mental health conditions.
  • Environmental risk factors can lead to changes in the brain that can make an individual more vulnerable to developing a mental health or SUD. Stress and childhood trauma, such as abuse or neglect, can contribute to the development of these conditions.

2. Mental health disorders can contribute to the development of substance use disorder (SUD)

Another possibility recognizes that mental health disorders can contribute to substance use as well as SUD. This is because individuals living with a mental health condition may turn to alcohol and other drugs to self-medicate their symptoms. While some prescription drugs can promote the health and well-being of individuals with mental health disorders, these medicines can only be obtained through a script written by a physician. Most people who use substances to self-medicate use illicit or recreational substances, which can more quickly develop into chemical dependency and addiction.

While some people may perceive temporary relief from their mental health symptoms by using alcohol and other drugs, self-medicating practices tend to worsen symptoms over time. Similarly, individuals who already struggle with mental health will likely perceive a higher reward from substance use, and this can lead to increased substance use.

3. Substance use can contribute to the development of mental health conditions

The last commonly held possibility is that substance use or SUD can contribute to the development of mental health conditions. This is because substance use can trigger alterations in brain functioning. Before a person can consciously realize it, their substance use may deteriorate their mental health and develop or worsen an additional mental health disorder.

Treating Co-Occurring Disorders and Substance Use

The most effective treatment plan for treating SUD co-occurring with another mental health condition is integrated treatment. Integrated treatment is different from treating SUD and mental health separately. With integrated treatment, both SUD and the co-occurring mental health disorder are treated simultaneously. In order for treatment to be successful, integrated treatment must be individualized. This means that an individual’s treatment plan must be tailored toward their specific symptoms and diagnosis. Individualized treatment allows every patient to feel validated and supported throughout their healing process.

Casa Palmera is an addiction treatment center that acknowledges that substance use disorder can develop from untreated mental health disorders and underlying mental health problems. We offer a program to treat co-occurring conditions using individualized and integrated treatment. Whether you are in need of detox or a residential treatment program, we offer a safe place of refuge and healing for everyone. To learn more about our treatment programs, contact us today.


This blog is for informational purposes only and should not be a substitute for medical advice. We understand that everyone’s situation is unique, and this content is to provide an overall understanding of substance use disorders. These disorders are very complex, and this post does not take into account the unique circumstances for every individual. For specific questions about your health needs or that of a loved one, seek the help of a healthcare professional.