Abuse potential and psychoactive effects of δ-9-tetrahydrocannabinol and cannabidiol oromucosal spray (Sativex), a new cannabinoid medicine.
There is a growing consensus that cannabis dependence is a substantial and underappreciated problem. The key component responsible for the euphoric effects of cannabis and its dependence potential is δ-9-tetrahydrocannabinol (THC). THC-containing cannabinoid medicines theoretically pose a risk of abuse and dependence. In order to evaluate the potential of Sativex to cause cannabis-like psychoactivity, abuse or dependence relevant data from all published papers have been reviewed along with the integrated safety analysis for Sativex use in multiple sclerosis (MS) patients on file at GW Pharmaceuticals. In clinical trials, intoxication scores have been low and euphoria reported by only 2.2% of patients. Tolerance has not occurred, abrupt withdrawal has not resulted in a formal withdrawal syndrome, and no cases of abuse or diversion have been reported to date. A formal abuse liability study of Sativex in experienced cannabis smokers showed some abuse potential in comparison with placebo at higher doses, but scores were consistently lower than equivalent doses of THC. Evidence to date suggests that abuse or dependence on Sativex is likely to occur in only a very small proportion of recipients.