Link Between Schizophrenia and Substance Abuse

Although schizophrenia is not a common mental illness, it is chronic and requires a lifetime of care and treatment. It is a serious disorder that disrupts how people think about and experience themselves and the world around them. Schizophrenia manifests in about 1 percent of the US population. Individuals who suffer from schizophrenia are at an increased risk of developing a substance addiction.

How Does Schizophrenia Start?

Symptoms typically begin between the ages of 16 and 30, although they have been known to manifest in those younger or older. There are several potential reasons the condition manifests, including heredity, biology, environment, altered brain chemistry (including from substance abuse), or even some viral infections.

There are three categories of symptoms demonstrated when a person is schizophrenic. These are:

  1. Cognitive: This group of symptoms includes anything that disrupts reasoning, attention, and memory. For example, a person will display poor executive function, have trouble focusing, and have problems with working memory (the ability to use information just after learning it).
  2. Positive: Symptoms considered positive are not good; rather, they are disturbances that are added to a person’s personality. These symptoms include hallucinations, delusions, unusual or dysfunctional ways of thinking, and agitated body movements.
  3. Negative: Symptoms of schizophrenia that are considered negative involve the removal of some aspect of a person’s personality, like taking less or no pleasure in daily life, having difficulty starting or maintaining activities, or reduced speaking. An easily identifiable symptom includes the flat effect, in which a person has less ability to express emotions through facial expression or voice tone.

Do Schizophrenics Have Higher Rates of Substance Use Disorder?

Substance abuse, also referred to as addiction, is also a disease of the brain, although it is considered different than mental illness. Addiction is a chronic disease in which the reward center of the brain changes how it processes mood-related neurotransmitters. This leads to compulsive consumption of intoxicating drugs, which the person struggling with addiction is unable to stop or control. Then, their body becomes dependent on the presence of the substance while also developing a tolerance, so they need to take more of the drug to receive the same effect.

People who struggle with substance abuse will display various symptoms, including:

  • Feeling the need to use the drug consistently
  • Experiencing intense urges or cravings for the drug
  • Needing more to get the same effect
  • Trying to stop but being unable to quit
  • Doing dangerous or illegal things like stealing, lying, or going to dangerous places to acquire the drug
  • Experiencing withdrawal symptoms if able to quit

A person who experiences a problem with substance abuse will likely struggle with employment, personal relationships, poor hygiene, declining health, and changes in behavior.

Like schizophrenia, a complex combination of genetic and environmental triggers can cause a person to develop a problem with substance abuse. Experimenting with drugs at an early age puts a person at risk for developing a substance use disorder. In addition, struggling with an undiagnosed mood disorder may cause a person to self-medicate with substances like alcohol, marijuana, heroin, or cocaine.

What are the Long-term Health Issues Associated With Schizophrenia and Substance Abuse?

As treatment for both schizophrenia and substance abuse has improved, people who struggle with one or both conditions experience better health and outcomes. Those who have either condition, or both co-occurring, can live fulfilling lives. However, they need to get help.

Untreated, schizophrenia can increase a person’s risk for developing chronic health problems. Some of these include:

  • Diabetes
  • Depression
  • Chronic unemployment
  • Homelessness
  • Unsatisfying or unsupportive relationships
  • Self-destructive behaviors, ranging from substance abuse to self-harm
  • Suicide

People who struggle with schizophrenia represent about 40 percent of those who are hospitalized due to psychotic symptoms, self-harm, delusions, and chronic health complications. Because they have access to fewer resources due to difficulty maintaining employment, housing, and relationships, people with schizophrenia are also less likely to get the treatment they need, increasing the risks of all health conditions.

Those who struggle with substance abuse are also likely to struggle with maintaining employment, housing, and healthy relationships. Depending on the substance being abused, the person may experience different long-term health problems, but abusing drugs for years severely damages the body and mind. People who have struggled with substance abuse may experience chronic health problems, including:

  • Respiratory infections, including pneumonia, tuberculosis, and bronchitis
  • Damage to the skin
  • Liver and kidney failure
  • Digestive problems, including ulcers, acid reflux, and malnutrition
  • Decline in cognitive function
  • Trouble with forming memories
  • Reproductive damage
  • Cancer
  • Viral infections, especially HIV or hepatitis

How Does Substance Abuse Affect Schizophrenia?

Mental and behavioral health are intimately connected. People who struggle with schizophrenia and a substance abuse problem may not know which occurred first; the answer is that either can occur first and then trigger the second condition. This is known as co-occurring disorders.

Substance abuse can sometimes be a trigger for schizophrenia. A person who is genetically inclined to develop schizophrenia, or whose brain chemistry may induce the condition, could experience a manifestation of the condition if they abuse some drugs; this is because schizophrenia is tied into a change in the levels of serotonin and dopamine, which are also affected by substance abuse. These include:

  • Marijuana
  • Cocaine
  • Amphetamines
  • Hallucinogens like LSD

However, people who struggle with schizophrenia are also at risk of developing substance abuse problems, sometimes to self-medicate. While the person may abuse drugs or alcohol due to a delusion about the substances, they may also try to heighten emotions or the experience of the world by ingesting intoxicating chemicals. Drugs commonly abused by people struggling with schizophrenia include:

  • Cannabis
  • Nicotine
  • Alcohol

There appears to be an inverse relationship between some drugs and schizophrenia; for example, people who struggle with heroin abuse are less likely to develop schizophrenia.

Some drugs, like marijuana, have a complex interplay between substance abuse and schizophrenia. Some research suggests that people who are predisposed to develop schizophrenia are more likely to find the high from cannabis pleasurable and therefore seek it out, often compulsively. However, because marijuana is a psychedelic drug, it can also trigger the development of schizophrenia because it floods the brain with neurotransmitters; when it is out of the body, those neurotransmitters have a hard time replenishing on their own. A study found that people who used marijuana about 50 times or more were over six times more likely than the general population to receive a diagnosis of schizophrenia. Another study found that adolescents who abused marijuana were 4.5 times more likely to struggle with schizophrenia by age 26 compared to their peers who did not abuse substances.

Stimulant drugs and hallucinogens also change how a person’s brain releases and absorbs neurotransmitters, making them more likely to trigger schizophrenia.

Alcohol is commonly abused among people with schizophrenia, likely to mitigate symptoms. One report suggests that up to 50 percent of people with schizophrenia have a co-occurring substance use disorder, and the most common substance abused is alcohol. However, people who struggle with schizophrenia also smoke cigarettes; they are three times more likely than the general population to struggle with addiction to nicotine. Alcohol and cigarettes are more commonly used to ease the symptoms of schizophrenia.

Additionally, people who struggle with schizophrenia are more likely to develop polydrug abuse problems. They are, for example, more likely to both drink alcohol and smoke marijuana.

What is Integrated Treatment for Co-occurring Disorders?

Integrated treatment for both substance abuse and mental illness is imperative to ensure people who struggle with both conditions achieve and maintain healthy lives. One step is for clinicians who work with people with schizophrenia to screen their clients for substance abuse problems. When a person admits to struggling with one substance, they can be screened for other substances of abuse with drug tests.

People who struggle with specific mental health problems, like schizophrenia or post-traumatic stress disorder, may benefit from receiving treatment through rehabilitation programs that focus only on their specific co-occurring disorders. This is true, also, of people who struggle with bipolar disorder, severe personality disorders, panic or anxiety disorders, and depression.

Ongoing evaluation of physical and mental health is an integral part of recovery for those who struggle with co-occurring addiction and schizophrenia. The individual may not know, remember, or believe that they have ingested an addictive substance while working on recovery, but their clinician can use a routine drug test to ensure the person is receiving the best possible combination of therapy, medication to treat schizophrenia, and complementary treatments to recover from substance abuse.

Unsure where to start? Take Our Substance Abuse Self-Assessment

Take our free, 5-minute substance abuse self-assessment below if you think you or someone you love might be struggling with substance abuse. This evaluation consists of 11 yes or no questions that are designed to be used as an informational tool to assess the severity and probability of a substance use disorder. The test is free, confidential, and no personal information is needed to receive the result. Please be aware that this evaluation is not a substitute for advice from a medical doctor.