Test Your Knowledge

The precise reasons why mental health disorders and substance abuse problems frequently occur together are not completely known, but many factors may be involved. Some professionals speculate that there may be a genetic factor that increases the risk of both mental illness and substance abuse. For example, both bipolar disorder and alcoholism may have a genetic component. The combination of mental illness and substance abuse is generally more common in women and among patients between the ages of 18 and 44 years. There is the possibility that the frequency may also reflect the misdiagnosis of symptoms of substance abuse as being those of another mental disorder.

Mental health conditions may be risk factors for substance abuse. Patients with mental illnesses may self-medicate in an attempt to treat the symptoms of their illness. This may occur both before and after diagnosis, regardless of whether the mental illness is being treated. Many substances (e.g., sedatives) can reduce a patient’s level of anxiety for at least a short while. Certain drugs (e.g., cocaine, amphetamines) may help to restrict food intake, effects that may be desirable for people with eating disorders. These patients may also use other substances (e.g., alcohol, other sedatives) to help counter the feelings of guilt or shame that may accompany the condition. When mental illness develops before a substance abuse problem, it may precede substance abuse by five to 10 years.

Problems adhering to certain social standards (e.g., behavior issues, keeping a steady job) occur in patients with mental illnesses. As a result, patients may end up living in areas with prevalent drug cultures. They may also find more acceptance of their behavior in social groups that revolve around drug use. This is known as “downward drift.” 

Both short- and long-term substance abuse (e.g., stimulants, hallucinogens) may produce symptoms similar to many mental illnesses. Many symptoms of substance intoxication are often associated with what appear to be symptoms of other mental disorders  (e.g., anxiety, paranoia, delusions). In some cases, these symptoms persist long after use of the substance has been halted. For example, the hallucinogen LSD may cause “flashbacks” years after the patient last abused the drug. The symptoms of these mental conditions are typically described as “substance-induced”. Certain consequences of lifestyles associated with substance abuse (e.g., failure at school or work, relationship problems, criminal involvement) may also lead to the development of mental health problems (e.g., depression).