Drug Abuse and Mental Illness

Drug abuse can cause a mental illness. Mental illness can lead to drug abuse. Drug abuse and mental disorders are both caused by other common risk factors.

How Common Are Comorbid Drug Abuse and Mental Disorders? The below chart shows a lifetime prevalence of drug disorders among persons with mood and anxiety disorders:

Drug abuse and mental disorders chart

  • Patients with mood or anxiety disorders are about twice as likely to also suffer from a drug disorder.
  • Patients with drug disorders are roughly twice as likely to be diagnosed with mood or anxiety disorders.

The high rate of comorbid substance abuse and mental illness points to the need for a comprehensive approach that identifies, evaluates, and simultaneously treats both disorders. Patients with co-occurring disorders often exhibit more severe symptoms than those caused by either disorder alone, underscoring the need for integrated treatment. Careful diagnosis and monitoring will help ensure that symptoms related to drug abuse (e.g., intoxication, withdrawal) are not mistaken for a discrete mental disorder. Even in people whose comorbidities do not occur simultaneously, research shows that mental disorders can increase vulnerability to subsequent drug abuse and that drug abuse constitutes a risk factor for subsequent mental disorders. Therefore, diagnosis and treatment of one disorder will likely reduce risk for the other, or at least improve its prognosis.


Problems with compliance

In mental health care, uncertainty about compliance is a challenging source of variation in the effectiveness of treatments. Noncompliance can represent a significant risk and cost to the medical system. For providers, partial compliance or discontinuation of medications represents the difficulty of maintaining treatment successes over time.


Compliance rates

Rates of compliance with mental health appointments are the greatest challenge (estimated in one hospital at 91%), while medication noncompliance is the second most challenging problem in the treatment of persons with mental illness. Mental health medication compliance can be determined by questioning patients, counting pills or prescriptions, and through drug monitoring with urine, blood, or other test measures. Overall, recent research estimates compliance to be 58%.

In an article, “Drug Therapy: Adherence to Medication,” in the New England Journal of Medicine, half of patients with major depression, for whom antidepressants have been prescribed, will not be taking the drugs three months after initiation of therapy. When adherence to drugs for physical diagnoses is compared with that for people with psychoses and depression, the mean rates are 76% compliance, 58% and 65%, respectively.


Driving Compliance

Many experts agree that non-compliance of medications by patients with behavioral health problems is affected by lack of immediate results; costs; problems filling a prescription; the stigma attached to drugs for mental health conditions; and by a lack of understanding about the nature of the illness and the drug’s side effects and effectiveness.


A Collaborative Approach

Addiction and Pain Research Institute of NY is an integrated medical-behavioral care program developed by ACLS for patients with chronic medical conditions who are also identified with behavioral issues. ACLS’s medication monitoring and drug detection services provide more than just test results to healthcare professionals treating people with chronic pain, mental illness and substance abuse disorder. We deliver the comprehensive scientific data backed by service and education necessary to clarify and reconcile results to make more informed clinical decisions for better patient outcome.