Delta-8-THC association with psychosis: A case report with literature review

BACKGROUND: Cannabis (Δ(9)-THC) is the most commonly consumed illicit drug. The Agricultural Improvement Act of 2018 removed hemp, a strain of Cannabis sativa, as a controlled substance. This law allowed the plant to be processed into its components, which contain <0.3% Δ(9)-THC. As a result, delta-8-tetrahydrocannabinol (Δ(8)-THC), a federally unregulated substance, grew in popularity in 2020. Δ(8)-THC is readily available in most gas stations or head shops and may be considered harmless by patients. However, an increasing number of patients admitted for psychiatric hospitalization report use, with limited literature on the effects. CASE PRESENTATIONS: This case report describes three individual cases of patients who required admission to a university psychiatric hospital after the regular use solely of Δ(8)-THC. All three patients developed psychotic and paranoid symptoms concurrently with the use of Δ(8)-THC, with a severity exceeding their previous historical presentations. The presenting psychotic symptoms were also atypical for all three patients. New-onset violence and visual hallucinations were noted in two of the patients, one patient with no previous psychiatric history and one patient while on a therapeutic dose of his antipsychotic. In the third case, a new onset of bizarre, fixed delusions of puppies dissolving in the bathtub developed. CONCLUSION: This report adds to the limited body of evidence on Δ(8)-THC documenting a temporal association between Δ(8)-THC use and the development of psychotic symptoms. A strong body of research already correlates the continued use of Δ(9)-THC with psychosis, and Δ(8)-THC acts at the same CB(1) and CB(2) receptors as Δ(9)-THC. Therefore, it is hypothesized that Δ(8)-THC may have similar adverse psychiatric effects as Δ(9)-THC. These conclusions are not without speculation, due to the need for self or collateral-reporting of Δ(8)-THC use as urine drug screening cannot distinguish Δ(8)-THC from Δ(9)-THC, and the patients' symptoms could be explained by medication non-adherence and primary psychotic disorders. However, physicians should be encouraged to gather a specific history of Δ(8)-THC use and treat patients with Δ(8)-THC-related intoxication and symptoms.