Evaluating Delta-8-THC-Induced Psychosis: A Systematic Review

This study reviews literature on the psychiatric effects of delta-8-THC, particularly psychosis and severe mental health outcomes, to highlight the need for further research and regulation.

Marijuana, the most widely used illicit drug in the United States, sees increasing use due to legalization. Although moderate use is generally safe, adverse effects can occur, especially in those with preexisting conditions. Delta-9-THC is known for its psychoactive effects and potential to induce psychosis. Delta-8-THC, another cannabinoid, is gaining popularity and has been linked to severe adverse events but remains under-researched.

A comprehensive search of PubMed and Web of Science followed PRISMA guidelines to identify studies and case reports on delta-8-THC and psychosis. Articles on delta-9-THC or other cannabinoids were excluded. Relevant studies were screened, and duplicates removed. The included studies were evaluated using the Critical Appraisal Skills Programme Checklist for Case Reports.

The search identified 201 studies, with 12 meeting the inclusion criteria for full-text analysis. Six case reports, involving 9 patients, were reviewed. Most patients were male and in their 20s, with varied psychiatric histories, including no prior psychiatric history, schizophrenia, posttraumatic stress disorder, and generalized anxiety disorder. Reported symptoms included psychosis, mood lability, and cannabinoid hyperemesis syndrome. Treatments varied, with different clinical outcomes.

Delta-8-THC poses significant psychiatric risks despite being less intoxicating than delta-9-THC. The lack of Food and Drug Administration regulation and the availability of delta-8-THC products heighten these risks. More rigorous studies are needed to understand delta-8-THC's impact on mental health and inform regulatory actions.