Hexahydrocannabinol and Hexahydrocannabiphorol Poisonings: Data From the Czech Toxicology Information Centre and Effects of Legislative Changes

Hexahydrocannabinol, a hydrogenated derivative of cannabinol, first came to the Czech Toxicological Information Centre (TIC) following reports of poisonings in May 2022. We conducted a retrospective observational study examining self‐reported cases of hexahydrocannabinol and hexahydrocannabiphorol exposure reported to the TIC from May 17, 2022, to April 30, 2024. Of 236 cases reported, 40 (17%) were excluded. The median age of patients was 18 years (range 1.5–73), with a male predominance of 55.8%. Notably, 39 children under 15 years constituted 19% of the cases. The primary exposure routes were ingestion (196 cases; 67.5%) and inhalation via smoking or vaping (62 cases; 31.5%). The clinical manifestations included neurological (74%), cardiovascular (43.1%), gastrointestinal (42.6%), psychiatric (21%), ocular (24.9%), and metabolic symptoms (14.7%). Physician intervention was required in 172 cases (87.8%). Severity assessment revealed mild symptoms in 119 patients (60.4%), moderate in 66 (33.5%), and severe in 12 (6.1%). Outcomes were favorable with recovery in 98% of cases; no fatalities were reported. Hexahydrocannabinol and hexahydrocannabiphorol exposures primarily resulted in neurological, cardiovascular, gastrointestinal effects, and other symptoms, with several cases being serious. Legislative changes impacting these poisonings require further evaluation.