Why Do Mental Health Disorders and Substance Abuse Coexist?

HHRC-Panic attack in public place. Woman having panic disorder.

Mental health comes first in achieving overall wellness. However, this may be more difficult for some people. According to the Substance Abuse and Mental Health Services Administration (SAMHSA), almost 9 million people suffer from a co-occurring mental health disorder and substance abuse disorder. Among those people, only 7% receive treatment for both conditions; nearly 60% receive no treatment.

Let’s learn how addiction affects mental health, why mental health disorders and substance abuse coexist, and the treatments available for those who need them.

What is Comorbidity?

Comorbidity is a situation where two conditions coexist, like a mental disorder and a substance abuse disorder. Although neither condition causes the other, they may worsen each other’s symptoms.

Is substance abuse a mental health disorder? Yes, and understanding that it is a mental disorder helps you understand comorbidity. A person struggling with addictions has their brain permanently rewired, altering their brain’s function. Like someone with heart disease or diabetes, addicts must manage their condition for life. However, this is not as easy as quitting drug or alcohol use.

Substance abuse also occurs in the same brain regions affected by depression and anxiety, schizophrenia, and bipolar disorder. This increases the comorbidity rate between substance abuse and mental health disorders. Their relationship may be complicated, but certain mental illnesses increase the likelihood of substance abuse. Problems with mental health cause some people to turn to drugs or alcohol to manage their symptoms.

Similarities Between Mental Health Disorders and Substance Abuse

Mental health and substance abuse disorders share many common traits. These include:

Both Are No-Fault Illnesses

One of the things substance abuse and mental disorders have in common is that they’re both no-fault illnesses. This means the person struggling with them isn’t at fault, nor did they choose to have this illness.

Recognizing that they didn’t choose this or wish it for themselves helps patients accept themselves more. Self-acceptance helps people to let go of their self-blame and take responsibility for their recovery, allowing them to start the journey to stability and wellness.

Both Are Stigmatized

Substance abuse and mental health disorder patients carry the stigma of these diseases. There are many stories in history about people who were disgraced or shunned for having a mental illness; for example, people often believe someone with epilepsy was “possessed” during the Middle Ages. They would be shunned and shamed because of the stigma of being “possessed” people have imposed, left to struggle with their disease on their own.

The stigma of substance abuse and psychiatric diseases is one imposed by society. Fortunately, these disorders are now more accepted than ever. Millions have recovered or are supporting their loved ones to recover, removing the stigma of these diseases and spreading correct information.

Both Cause Isolation

Isolation is another trait that substance abuse and mental health disorders share. Some people often keep their troubling thoughts, emotions, and behaviors to themselves. However, this can lead to isolation, making them believe they are the only person experiencing these thoughts and emotions.

Both Are Chronic Brain Disorders

Evidence points out that disturbances in brain chemistry can cause brain disorders and addiction. Both are mental health disorders that persist and linger, sharing many factors like genetics and behaviors like denial, shame, and guilt.

Similar Treatment Paths

Lastly, both illnesses have similar treatment and rehabilitation phases, including acute stabilization, treatment engagement, and maintenance. Treatments must address both mental and physical symptoms to achieve harm reduction or abstinence.

Why Mental Health Disorders and Substance Abuse Co-occur

According to the National Institute on Drug Abuse, there are many factors to consider as to why they coexist. Some of them include the following:


Some evidence suggests that problems with mental health and addiction are caused by genetics, brain defects, or early trauma exposure. Genetics alone is responsible for 40-60% of an individual’s vulnerability to addiction. Certain regions in the human genome are also linked to increased risk for substance abuse and mental illness.


The age when the symptoms first appear is another common factor in mental health problems and addiction. Adolescence is a time when people are still growing and developing and when brain development and maturation are at their peak. However, it’s also a time when a person is more impulsive and ready to take chances. This makes them more likely to engage in risky behaviors that increase the likelihood of developing an addiction or mental disorder.


People who have experienced physical or emotional trauma are more likely to develop substance abuse or mental health disorders. This is especially true for veterans returning home from war.

Treatments for Coexisting Mental Health Disorders and Substance Abuse

Research shows that mental health and addiction treatment should coincide. Integrated treatment for addiction and mental issues allows doctors and counselors to address both disorders simultaneously, resulting in lower treatment costs and better outcomes.

The best thing to do is to get treatment for both conditions as early as possible. This can significantly affect a patient’s quality of life and recovery. Patients with both disorders often experience more severe and persistent symptoms that are difficult to treat than those with only one disorder. Maintaining sobriety is also more challenging for them.

The Bottom Line

Mental health comes first, but it may not be easy for people with co-occurring substance abuse and mental health disorders. Substance abuse alters a person’s brain, increasing their chances of developing a mental health disorder. Meanwhile, mental health disorders push some people to use alcohol or drugs to self-medicate or manage their symptoms. Genetics, age, and trauma also influence both conditions. Treatment for both disorders should coincide to produce better outcomes.

Help is within your reach at Haven House.

Our center for addiction recovery in Santa Rosa Beach, FL, accepts all needing help, regardless of their background. We provide a 12-step program integrated into faith-based rehabilitation that provides a supportive environment. We ensure a safe space for sharing and healing that can help you feel motivated on your journey to sobriety. We also help keep relapse at bay and support when relapse does occur.

Help is always within your reach with us. Call our center today to schedule a pick-up or for any questions about our programs.