HHC-induced psychosis in adolescents: a case series
Piril Cevikel, Joana Ferreira, Eamon Raji, Catherine O’brien, Brian P. Hallahan
Irish Journal of Psychological Medicine June 19, 2026 DOI: 10.1017/ipm.2026.10201 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Case study Case report Peer reviewed |
|---|---|
| Sample size | 2 |
| Population | Adolescents with HHC-induced psychosis and no prior psychiatric history |
| Duration | About six weeks of inpatient treatment |
| Keywords | Psychosis Abstinence Antipsychotic Schizophrenia object-oriented programming Medline |
| Key findings | HHC use can trigger psychosis in adolescents without prior psychiatric history, requiring extended inpatient treatment and resolving with abstinence and antipsychotics. |
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.
Citations in the library
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