HHC-induced psychosis in adolescents: a case series

Abstract

Hexahydrocannabinol (HHC) is a semi-synthetic cannabinoid that recently emerged as a legal alternative to Δ9-tetrahydrocannabinol. Due to emerging concerns regarding its neuropsychiatric safety profile, including psychosis, it was banned in July 2025. We report two cases of HHC-induced psychosis in adolescents requiring inpatient psychiatric admission, both with no prior psychiatric history. Both individuals required about six weeks of inpatient treatment, with their symptoms resolving following abstinence from HHC and antipsychotic medications. These cases support recent regulatory measures banning HHC and highlight the need for ongoing clinician awareness of this agent and its associated risk of psychosis.