The effects of substance use are not always outwardly visible. Many people who suffer from substance use disorders (SUD) also experience mental health effects like paranoia, depression, anxiety, aggression, hallucinations and other problems. Furthermore, studies have found that approximately half of the individuals with a substance use disorder are diagnosed with a mental health disorder and vice versa. 

Dealing with a substance use disorder and a co-occurring disorder like anxiety, depression or another disorder can make you feel isolated. However, you are not alone, and there is always hope. If you need an ally, our team at Seneca Health Services is here for you. Read on to learn more about the mental health effects of substance use.

What is a Co-Occurring Disorder?

The Substance Abuse and Mental Health Services Administration (SAMHSA) defines a co-occurring disorder as the coexistence of a substance use disorder and a mental health disorder. Co-occurring disorders are common and can affect anyone, no matter their age or background.

Sometimes, it is challenging to tell whether you have a co-occurring disorder. If you are unsure, ask yourself these questions from Help Guide

  • Do you use substances to cope, control pain or strong moods, face frightening situations or stay focused on tasks?
  • Have you noticed a relationship between substance use and your mental health? 
  • Has someone in your family dealt with a mental disorder or a substance use disorder?
  • Do you feel depressed, anxious or otherwise out of balance even when you are sober?
  • Have you previously been treated for a substance use disorder or a mental health disorder? 

If you answered “yes” to any of these questions, we encourage you to reach out and ask for help. Seeking professional help is the beginning step on the road to recovery. 

What Causes a Co-Occurring Disorder?

While there is no definitive answer to which one causes the other, the National Institute of Mental Health (NIMH) suggests three possibilities to explain why substance use disorders and mental health disorders often occur together: 

  • Mental health disorders can contribute to substance use disorders:  Research has found that people with anxiety, depression and post-traumatic stress disorder (PTSD) may turn to substances as a form of self-medication. However, this often ends up having the opposite effect. For instance, many substances worsen symptoms over time. Furthermore, the rewarding nature of substances can cause brain changes, which can cause someone to develop a substance use disorder in the future. 
  • Substance use disorders can contribute to mental health disorders: Over time, substance use can change the structure and function of the brain, which may cause someone to develop a mental health disorder. 
  • There are common risk factors: Substance use disorders and mental health disorders tend to run in families. Therefore, this fact suggests that a combination of genetic and environmental factors may contribute to someone developing a co-occurring disorder. If you would like to learn more about why substance use disorders often affect families throughout multiple generations, check out our blog, Behavioral Health: Can Substance Use Patterns Be Passed Down to Your Children? 

What Are the Mental Health Effects of Substance Use?

Below are some examples of substances that SAMHSA states can cause mental health problems.


Alcohol abuse can cause health problems, social problems or both. The dangerous, short-term psychological effects of alcohol abuse include altered perceptions and emotions. 

Alcoholism is a disease characterized by the inability to control drinking. This study states that depression, bipolar disorder, anxiety, antisocial personality disorder (ASPD) and other externalizing disorders are often related to alcoholism.


Methamphetamine (also called “speed,” “meth” or “crank”) is a stimulant drug chemically related to amphetamine. The psychological effects of methamphetamine include irritability, confusion, anxiety, paranoia and violent behavior.


Cocaine is a stimulant drug. Stimulant drugs tend to give a temporary illusion of limitless power and energy, but this only leaves the user feeling depressed, edgy and desiring more. Some psychological effects of cocaine include violent, erratic and paranoid behavior. Hallucinations, confusion, anxiety, depression and cocaine psychosis are also additional side effects.


Hallucinogenic drugs are substances that distort reality. Phencyclidine (PCP), angel dust, lysergic acid diethylamide (LSD), mescaline, peyote and psilocybin (“magic” mushrooms) are all types of hallucinogenic drugs. Some psychological effects of hallucinogens include estrangement depression, anxiety and paranoia. Additional side effects include violent behavior, confusion, suspicion, loss of control of behavior and psychosis catatonic syndrome.


Marijuana (weed) tends to be the first substance that many teenagers use. The psychological side effects of marijuana include paranoia and hallucinations. According to the National Institute on Drug Abuse, psychosis (schizophrenia), depression, anxiety and substance use disorders could be linked to marijuana, but it is challenging to make an exact determination. 

Other Substances 

Some other substances that can cause mental health problems include: 

  • Inhalants
  • Ketamine
  • Kratom
  • MDMA
  • Prescription drugs
  • Steroids 

Find Treatment at Seneca Health Services

If you or someone you know is struggling with a substance use disorder, a mental health disorder or a co-occurring disorder, Seneca Health Services can help. We provide a holistic approach to substance use and mental health treatment. We begin each episode of treatment with an individual assessment by a qualified behavioral health clinician. Our staff will listen to you, support you and will not provide any more or less treatment than what is needed.

Furthermore, we believe that treatment for co-occurring disorders should happen simultaneously. Our medical professionals are experienced with all aspects of behavioral health. They can address substance use disorders, and they can also treat co-occurring disorders, such as mood or anxiety disorders. If you have any questions, please do not hesitate to contact the Seneca office nearest you

Greenbrier County, West Virginia: (304) 497-0500

Nicholas County, West Virginia: (304) 872-2659

Pocahontas County, West Virginia: (304) 799-6865

Webster County, West Virginia: (304) 847-5425