Psychedelic symptoms of cannabis and cocaine use as a function of trait impulsivity

Regular drug users with normal or high trait impulsivity levels showed largely similar subjective responses to cocaine, cannabis, and placebo. Cannabis increased dissociation, psychedelic symptoms, fatigue, confusion, depression, and anxiety while decreasing arousal, positive mood, vigor, friendliness, and elation. Cocaine increased dissociation, psychedelic symptoms, vigor, friendliness, elation, positive mood, anxiety, and arousal while decreasing fatigue. Only a few subjective measures differed by impulsivity level; psychedelic symptoms were most intense in high-impulsivity subjects. Trait impulsivity correlated negatively with vigor (r = -.197) and positively with loss of thought control (r = .237) during cannabis intoxication, but a broad association between trait impulsivity and psychedelic drug experience was absent.

Study at a glance

Abstract

Trait impulsivity has been linked to addiction in humans. It has been suggested that drug users with high trait impulsivity levels are more sensitive to subjective drug intoxication. This study assessed whether subjective response to drugs differs between drug users with normal or high levels of trait impulsivity. Regular drug users (N = 122) received doses of cocaine HCl, cannabis, and placebo in a three-way crossover study. Their mood, dissociative state, and psychedelic symptoms were measured with subjective rating scales (CADDS, Bowdle, POMS). Trait impulsivity was assessed with the Barratt Impulsiveness Scale. Cannabis increased dissociation and psychedelic state, as well as fatigue, confusion, depression and anxiety, and decreased arousal, positive mood, vigor, friendliness, and elation. Cocaine increased dissociation, psychedelic state, vigor, friendliness, elation, positive mood, anxiety and arousal, while decreasing fatigue. Only a few subjective items revealed a drug × trait impulsivity interaction, suggesting that psychedelic symptoms were most intense in high impulsivity subjects. Trait impulsiveness ratings were negatively correlated with ratings of vigor (r = -.197) and positively correlated with ratings of loss of thought control (r = .237) during cannabis intoxication. It is concluded that a broad association between trait impulsivity and psychedelic subjective drug experience appears to be absent.