Schizophrenia and Substance Abuse

Schizophrenia and substance abuse are closely linked.  Schizophrenia and alcohol abuse is particularly common. Discover why.

Mental illness and drugs are linked and schizophrenia and substance abuse particularly so. While most researchers believe that substance abuse does not cause schizophrenia, people with schizophrenia are much more likely to suffer from drug abuse.

  • About half of those with schizophrenia may abuse drugs and alcohol

Not only is substance abuse inherently problematic in the schizophrenic’s life but substance abuse can also negatively affect how prescription drugs for schizophrenia work. It has also been shown that people with schizophrenia who abuse drugs are also much less likely to stick to a treatment plan. Many street drugs like cocaine and meth are known to worsen schizophrenia symptoms. And while scientists believe there is drug-induced psychosis, it’s unlikely that there is drug-induced schizophrenia.

Schizophrenia and substance abuse is more common:

  • Among men
  • Among those in institutional settings like hospitals, jails and homeless shelters

The above correlations are not confined to those with schizophrenia, however.

Schizophrenia and Alcohol

Schizophrenia and drug abuse are common. Alcohol is the drug most commonly abused, aside from nicotine, with possibly more than one-in-three people with schizophrenia being an alcoholic at some time in their life.1

People with schizophrenia likely use alcohol for the same reasons everyone else does but they have additional biological, psychological and environmental factors weighing on them making schizophrenia and alcoholism more prevalent.

Additional factors that may affect schizophrenia and alcohol abuse include:

  • Self-medication of the symptoms of schizophrenia and related life factors with alcohol
  • Encouragement of alcohol use and abuse due to abnormalities in the schizophrenic brain
  • Easier development of the behaviors that lead to substance abuse due to cognitive impairment typical of schizophrenia
  • Use of alcohol to create a social circle

Unfortunately, schizophrenia and alcohol are correlated with poorer treatment outcomes. People who are known to have schizophrenia and substance abuse issues have:

  • More schizophrenia symptoms and symptom recurrence
  • Social and life instability, including homelessness
  • Other substance use disorders
  • Issues with violence
  • Legal problems
  • Medical problems
  • More time spent in institutions like jails and hospitals

Schizophrenia and Smoking

Smoking is the most common substance abuse problem in people with schizophrenia. People with schizophrenia are addicted to nicotine at three times the rate of the average person:

  • 75% - 90% of people with schizophrenia are addicted to nicotine compared with 25% - 30% of the general population2

The relationship between smoking and schizophrenia is complex as nicotine acts on various chemical messengers in the brain that affect schizophrenia and psychosis. It is thought this may make smoking more pleasurable and more addictive to a person with schizophrenia. However, nicotine may negatively impact schizophrenia medication (antipsychotics).

Quitting smoking can be very difficult for someone with schizophrenia because nicotine withdrawal can cause a temporary worsening of psychotic symptoms. Nicotine replacement withdrawal strategies may make it easier for a person with schizophrenia to quit abusing nicotine.

article references

APA Reference
Tracy, N. (2021, December 20). Schizophrenia and Substance Abuse, HealthyPlace. Retrieved on 2024, May 19 from

Last Updated: March 25, 2022

Medically reviewed by Harry Croft, MD

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