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Causes of Psychosis

mindfulness-cultivating-resilienceWhen my son Dan was diagnosed with severe obsessive-compulsive disorder, his psychiatrist informed me and my husband that Dan was “borderline psychotic.” In other words, our son was out of touch with reality. For most people, psychosis usually presents in one of two ways:

  • Hallucinations – consist of seeing, hearing or feeling things that are not actually there. A common example is hearing voices.
  • Delusions – consist of beliefs that are not likely to be true and that seem irrational or nonsensical to other people. A typical example involves believing that outside forces are controlling your thoughts, feelings, and behaviors.

At the time we were told of our son’s issues, my thoughts immediately turned to schizophrenia, as that is the illness typically associated with psychosis. And indeed, psychosis is one of the major symptoms of schizophrenia. Because he was borderline psychotic, did my son have schizophrenia in addition to OCD?

First, it is important to understand that psychosis, in and of itself, is not an illness. It is a symptom. Just as coughing can be a symptom of anything from post-nasal drip to air pollution to lung cancer, psychosis is usually part of a bigger picture.

Schizophrenia is one possibility, and certainly the most common. Below is a list (by no means exhaustive) of some other illnesses or circumstances that might lead to psychosis:

  • Brain disorders. In addition to schizophrenia, illnesses such as bipolar disorder, depression, Alzheimer’s, dementia, and obsessive-compulsive disorder might involve psychotic experiences.
  • Trauma. Experiencing violence of any sort (rape for example) or witnessing a horrific event (such as a fatal car accident) are some examples of trauma.
  • Physical injury. Traumatic brain injuries can cause psychosis.
  • Illness. Some illnesses that might lead to psychosis include strokes, brain tumors, HIV, Huntington’s disease, and Parkinson’s disease. Indeed any illness that involves brain inflammation, including PANDAS and Lyme disease, can lead to psychosis.
  • Sleep disturbances/hormones. Postpartum psychosis typically occurs within two weeks of giving birth and might be related to changes in hormone levels and interrupted sleep patterns.
  • Substance abuse. Some people experience psychosis as a result of using LSD, amphetamines, and marijuana.
  • Genetic disposition. It is possible that genes contribute to the development of psychosis, and researchers continue to study this area.

Back to my son Dan. His “borderline psychotic” symptoms were in the form of delusions — believing things such as if he didn’t tap a wall ten times, something horrible would happen to someone he loved. During his worst moments he truly believed this, but at other times he realized how irrational his thinking was. Thankfully, once Dan’s OCD was appropriately treated, he once again became firmly grounded in reality. No more psychosis.

So what should you do if you or a loved one experiences symptoms of psychosis? All the experts agree that getting a proper diagnosis and subsequent appropriate help as soon as possible is of the utmost importance. The earlier psychosis is addressed, either with medication, therapy, or both, the better the chances are for a positive outcome.


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Causes of Psychosis

Janet Singer

Janet Singer’s son Dan suffered from OCD so severe that he could not even eat. After navigating through a disorienting maze of treatments and programs, Dan made a triumphant recovery. Janet has become an advocate for OCD awareness and wants everyone to know that OCD, no matter how severe, is treatable. There is so much hope for those with this disorder. Janet, who uses a pseudonym to protect her son’s privacy, is the author of Overcoming OCD: A Journey to Recovery, published in January 2015 by Rowman & Littlefield. Her own blog,, has reached readers in 167 countries. She is married with three children and resides in New England.

APA Reference
Singer, J. (2018). Causes of Psychosis. Psych Central. Retrieved on October 1, 2020, from
Scientifically Reviewed
Last updated: 8 Oct 2018 (Originally: 22 Apr 2017)
Last reviewed: By a member of our scientific advisory board on 8 Oct 2018
Published on Psych All rights reserved.