Cannabis and tolerance: acute drug impairment as a function of cannabis use history
Johannes G. Ramaekers, J. H. van Wel, Desirée Spronk, Stefan W. Toennes, Kim P. C. Kuypers, Eef L. Theunissen, Robbert J. Verkes
Scientific Reports May 26, 2016 DOI: 10.1038/srep26843 via OpenAlex
Summary
AI-generated from the abstractAcute cannabis intoxication impairs executive function, impulse control, attention, and psychomotor function, and increases subjective intoxication, regardless of how frequently a person uses cannabis. In a study of 122 drug users with cannabis use histories ranging from infrequent to daily, cannabis (300 μg/kg THC) produced these deficits compared to placebo, while cocaine (300 mg) improved psychomotor function and attention but impaired impulse control. The absence of tolerance to cannabis's neurocognitive effects suggests that frequent use and intoxication can interfere with performance in daily environments such as school, work, or traffic.
Study at a glance
| Characteristics | Randomized controlled trial Peer reviewed |
|---|---|
| Sample size | 122 |
| Population | Drug users with cannabis use history ranging from infrequent to daily |
| Interventions | Cannabis (300 μg/kg THC) cocaine HCl (300 mg) |
| Dose | 300 μg/kg THC for cannabis; 300 mg for cocaine HCl |
| Topics | Cannabis |
| Keywords | Drug tolerance Medicine Psychiatry Medline |
| Citations | 81 |
| Key finding | Acute cannabis intoxication impairs neurocognitive performance similarly across users regardless of cannabis use history, indicating no tolerance to these effects. |
Abstract
Cannabis use history as predictor of neurocognitive response to cannabis intoxication remains subject to scientific and policy debates. The present study assessed the influence of cannabis on neurocognition in cannabis users whose cannabis use history ranged from infrequent to daily use. Drug users (N = 122) received acute doses of cannabis (300 μg/kg THC), cocaine HCl (300 mg) and placebo. Cocaine served as active control for demonstrating neurocognitive test sensitivity. Executive function, impulse control, attention, psychomotor function and subjective intoxication were significantly worse after cannabis administration relative to placebo. Cocaine improved psychomotor function and attention, impaired impulse control and increased feelings of intoxication. Acute effects of cannabis and cocaine on neurocognitive performance were similar across cannabis users irrespective of their cannabis use history. Absence of tolerance implies that that frequent cannabis use and intoxication can be expected to interfere with neurocognitive performance in many daily environments such as school, work or traffic.