A Cautious Reminder about the Potential Risk of Psychosis When Cannabis Is Used as a Treatment for Chronic Pain

Abstract

Fibromyalgia is a neurological condition caused by glutamate dysregulation which leads to central sensitization. It is characterized by chronic widespread pain, fatigue, headache/migraine, sleep issues, and cognitive dysfunction, and is commonly comorbid with gastrointestinal symptoms, depression, and anxiety. Due to a lack of widespread effective treatment options, many patients are seeking out cannabis as a treatment, though little is known about the contraindications for its use.

This case study presents information on a non-Hispanic 27-year-old African American woman with fibromyalgia and schizoaffective disorder who was using cannabis as a treatment for her pain. She was put on the low glutamate diet to treat her fibromyalgia, which significantly reduced her pain and other symptoms after one month, allowing her to discontinue the use of the cannabis. This discontinuation in turn drastically reduced her psychiatric symptoms. Her case is presented along with a discussion on the glutamatergic mechanisms which may be responsible for this effect, known side effects of cannabis, and potential contraindications for its use.

This case study demonstrates that while cannabis may have pain relieving properties, it can also increase the likelihood of psychosis. In this case study, there was no safe daily dosage of cannabis noted. After experiencing symptom relief from the low glutamate diet, the patient discontinued the use of cannabis which led to further psychiatric improvements. The literature suggests that this adverse effect appears to be mediated by glutamate and may be more pronounced with early age of use, increasing dosage, high potency, and in those who may be predisposed to psychiatric illness. Physicians should inquire about self-treatment with cannabis in individuals being treated for pain who present with comorbid psychiatric illness, especially psychotic symptoms.