Hexahydrocannabinol (HHC) use and harms in Ireland: New findings from the 2024 European Web Survey on Drugs.
The International journal on drug policy November 1, 2025 Deirdre Mongan, Nicki Killeen, Seán R Millar et al.
Hexahydrocannabinol (HHC), a semi-synthetic cannabinoid sold openly in Ireland as a legal cannabis alternative until July 2025, has become a prominent feature of the Irish drug landscape. Among 2,314 adults who had used drugs in the past year, 36.2% reported lifetime HHC use, 33.5% past-year use, and 17.8% past-month use. The main reason for first trying HHC was its easy availability in stores, with 62.4% obtaining it from high street shops. Negative consequences were reported by 89.9% of users, including anxiety or panic (14.7%), faintness or dizziness (13.4%), dissociation or depersonalisation (11.9%), hallucinations or psychosis (3.9%), depression (3.6%), and withdrawal symptoms (3.2%). The findings indicate HHC poses public health concerns and requires monitoring.