Understanding the Link Between Addiction and Schizophrenia

Drug addiction and schizophrenia can feel pretty similar. And if you have both, it might be hard to tell where one condition ends and the other begins. Learning about that dynamic is a key part of recovery. That knowledge can empower you to find the right type of treatment for schizophrenia and substance abuse.

Does Drug Addiction Cause Schizophrenia?

In short: no, taking drugs won’t give you schizophrenia. But addiction and schizophrenia have similar causes ((Khokhar, J. Y., Dwiel, L., Henricks, A., Doucette, W. T., & Green, A. I. (2018). The link between schizophrenia and substance use disorder: A unifying hypothesis. Schizophrenia Research, 194, 78–85. https://doi.org/10.1016/j.schres.2017.04.016))—and similar symptoms. The same factors that make you vulnerable to one can also make you vulnerable to the other.

If you have schizophrenia, drug use can trigger your symptoms. ((Causes—Schizophrenia. (2021, February 12). Nhs.Uk. https://www.nhs.uk/mental-health/conditions/schizophrenia/causes/)) And depending on what drug you’re taking, being high can even feel like psychosis. ((Fiorentini, A., Cantù, F., Crisanti, C., Cereda, G., Oldani, L., & Brambilla, P. (2021). Substance-induced psychoses: An updated literature review. Frontiers in Psychiatry, 12, 694863. https://doi.org/10.3389/fpsyt.2021.694863)) That’s because both drug use and schizophrenia tamper with your brain’s reward system. ((Powledge, T., Addiction and the brain: The dopamine pathway is helping researchers find their way through the addiction maze, BioScience, Volume 49, Issue 7, July 1999, Pages 513–519, https://doi.org/10.2307/1313471)) Here’s why.

The Similar Brain Chemistry of Schizophrenia and Addiction

Taking any drug has an impact on your brain’s reward system. ((Powledge, T., Addiction and the brain: The dopamine pathway is helping researchers find their way through the addiction maze, BioScience, Volume 49, Issue 7, July 1999, Pages 513–519, https://doi.org/10.2307/1313471)) And it doesn’t matter what the drug’s actual effects are. The very act of getting high increases your levels of dopamine, a neurotransmitter. So when you take drugs, you feel a sense of reward.

Over time, you’ll need more and more of a drug to achieve that feeling. Reward might be replaced with relief. And as your tolerance goes up, you’ll likely develop a more severe addiction.

Even if you never take drugs, schizophrenia still disrupts your reward system. ((Khokhar, J. Y., Dwiel, L., Henricks, A., Doucette, W. T., & Green, A. I. (2018). The link between schizophrenia and substance use disorder: A unifying hypothesis. Schizophrenia Research, 194, 78–85. https://doi.org/10.1016/j.schres.2017.04.016)) In some people, it decreases baseline levels of dopamine. Or, it can make you hypersensitive to dopamine, so doing drugs feels like an even bigger reward. And if you’re taking drugs that reduce the symptoms of schizophrenia, ((Potvin, S., et al. “[Schizophrenia and addiction: An evaluation of the self-medication hypothesis.” L’Encephale, vol. 29, no. 3 Pt 1, May 2003, pp. 193–203.)) addiction is even more likely.

Self-Medicating to Manage Schizophrenia

While addiction is unhealthy, it often begins as a coping mechanism. You might feel like drug use helps you control the symptoms of schizophrenia. ((Batel, P. (2000). Addiction and schizophrenia. European Psychiatry, 15(2), 115–122. https://doi.org/10.1016/S0924-9338(00)00203-0)) And, in some cases, that might even be true. For example, nicotine reduces psychotic symptoms. ((Quigley, H., & MacCabe, J. H. (2019). The relationship between nicotine and psychosis. Therapeutic Advances in Psychopharmacology, 9, 2045125319859969. https://doi.org/10.1177/2045125319859969)) But that doesn’t mean cigarettes are good for you.

In the long term, addiction continues to destabilize your reward system. Because of this, ongoing drug use can exacerbate your schizophrenia symptoms. This complicates the process of recovery.

Treatment for Both Schizophrenia and Addiction

Quitting drugs isn’t a cure for schizophrenia. ((“Schizophrenia.” World Health Organization. https://www.who.int/news-room/fact-sheets/detail/schizophrenia. Accessed 9 Jan. 2023.)) But for some people, it’s an important first step toward healing. And because of the overlap between addiction and schizophrenia, ((Gouzoulis-Mayfrank, Euphrosyne, and Marc Walter. “Schizophrenia and Addiction.” Co-Occurring Addictive and Psychiatric Disorders: A Practice-Based Handbook from a European Perspective, edited by Geert Dom and Franz Moggi, Springer, 2015, pp. 75–86. Springer Link, https://doi.org/10.1007/978-3-642-45375-5_6.)) many of the same treatments might help with all your symptoms.

If you’re recovering from both these conditions, you might benefit from treatment for co-occurring disorders. Within that framework, there are several specific therapies that can help.

Motivational Interviewing

Motivational interviewing (MI) helps patients with schizophrenia ((Fiszdon, Joanna M., et al. “Motivational Interviewing to Increase Cognitive Rehabilitation Adherence in Schizophrenia.” Schizophrenia Bulletin, vol. 42, no. 2, Mar. 2016, pp. 327–34. PubMed Central, https://doi.org/10.1093/schbul/sbv143.)) commit to ongoing treatment. It’s an especially effective treatment for people with both addiction and psychosis. ((Bagøien, G., Bjørngaard, J. H., Østensen, C., Reitan, S. K., Romundstad, P., & Morken, G. (2013). The effects of motivational interviewing on patients with comorbid substance use admitted to a psychiatric emergency unit—A randomised controlled trial with two year follow-up. BMC Psychiatry, 13(1), 93. https://doi.org/10.1186/1471-244X-13-93))

MI isn’t technically a type of therapy. Instead, it’s a conversation style that many different clinicians apply to treatment. Therapists, doctors, nurses, and others can all use this approach. During MI, they’ll use active listening, pointed questions, and other techniques. This can help you find your personal spark of motivation to heal.

Contingency Management

For patients with both schizophrenia and addiction, contingency Management (CM) can make recovery more likely. ((Adams, Claire E., et al. “Contingency Management for Patients with Cooccurring Disorders: Evaluation of a Case Study and Recommendations for Practitioners.” Case Reports in Psychiatry, vol. 2012, Jan. 2012, p. e731638. www.hindawi.com, https://doi.org/10.1155/2012/731638)) This approach rewards your participation in treatment. For example, you might get a gift card, voucher, or even cash for going to a therapy session. You and your care team will write and honor a treatment contract, defining prizes for each activity. In most cases, the value of your rewards will go up over time. For many people, this agreement motivates positive changes.

Dialectical Behavioral Therapy

Dialectical behavioral therapy (DBT) was originally developed to treat borderline personality disorder. Today, it has many additional uses. For example, DBT can help patients with schizophrenia, ((Kemp, Cheyenne (2018) “Dialectical Behavior Therapy as a Possible Treatment Modality for Schizophrenia,” Intuition: The BYU Undergraduate Journal of Psychology: Vol. 13 : Iss. 1 , Article 7.)) addiction, and other mental health conditions.

Sessions of DBT can feel more like classes than therapy. You’ll meet with a group, go through a workbook, and even do homework. You might also have 1:1 sessions with your therapist. Patients learn practical skills in 4 modules: mindfulness, interpersonal effectiveness, emotion regulation, and distress tolerance. These coping strategies can empower you to live a healthier life.

Cognitive Behavioral Therapy

Like DBT, cognitive behavioral therapy (CBT) focuses on practical coping skills. CBT helps patients with addiction and schizophrenia ((Morrison, A. K. (2009). Cognitive behavior therapy for people with schizophrenia. Psychiatry (Edgmont), 6(12), 32–39. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2811142/)) manage their symptoms without drug use.

Instead of trying to change your feelings, CBT shows you new ways to respond. Future episodes of psychosis might always trigger drug cravings. But you’ll learn how to accept that feeling and move on, instead of falling back into addiction.