[Effects of oral cannabis and dronabinol on driving capacity].
Christian Giroud, Marc Augsburger, Bernard Favrat, Annick Ménétrey, Marie A. Pin, Laura E. Rothuizen, Monique Appenzeller, Thierry Buclin, S Mathieu, V Castella, A Hazekamp, Patrice Mangin
Annales pharmaceutiques francaises May 2006 DOI: 10.1016/s0003-4509(06)75309-3 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Double-blind crossover study Peer reviewed |
|---|---|
| Sample size | 8 |
| Population | Healthy male occasional cannabis smokers, aged 22 to 30 years |
| Interventions | Dronabinol cannabis milk decoction placebo |
| Dose | 20 mg dronabinol, 16.5 mg THC, 45.7 mg THC |
| Duration | Treatments administered at two week intervals |
| Measures | visual analog scale, psychomotor test, tracking test on a driving simulator, blood concentrations of THC, 11-OH-THC and THC-COOH, genetic polymorphism of catechol-O-methyltransferase, Cannabis Influence Factor (CIF) |
| Topics | Cannabis |
| Key points | Oral THC produced low blood concentrations of THC and metabolites compared with smoking. Two participants experienced deep anxiety, which the authors suggest may occur when driving under the influence of cannabis. Driving willingness varied with task importance, and road sign and tracking performance was greatly impaired, especially after the strongest dose. The Cannabis Influence Factor (CIF) provided a good estimate of fitness to drive. |
Abstract
Two retrospective epidemiologic studies have shown that cannabis is the main psychoactive substance detected in the blood of drivers suspected of driving under the influence of psychotropic drugs. An oral administration double-blind crossover study was carried out with eight healthy male subjects, aged 22 to 30 years, all occasional cannabis smokers. Three treatments and one placebo were administered to all participants at a two week interval: 20 mg dronabinol, 16.5 mg D9-tétrahydrocannabinol (THC) and 45.7 mg THC as a cannabis milk decoction. Participants were asked to report the subjective drug effects and their willingness to drive under various circumstances on a visual analog scale. Clinical observations, a psychomotor test and a tracking test on a driving simulator were also carried out. Compared to cannabis smoking, THC, 11-OH-THC and THC-COOH blood concentrations remained low through the whole study (<13.1 ng THC/mL,<24.7 ng 11-OH-THC/mL and<99.9 ng THC-COOH/mL). Two subjects experienced deep anxiety symptoms suggesting that this unwanted side-effect may occur when driving under the influence of cannabis or when driving and smoking a joint. No clear association could be found between these adverse reactions and a susceptibility gene to propensity to anxiety and psychotic symptoms (genetic polymorphism of the catechol-O-methyltransferase). The questionnaires have shown that the willingness to drive was lower when the drivers were assigned an insignificant task and was higher when the mission was of crucial importance. The subjects were aware of the effects of cannabis and their performances on the road sign and tracking test were greatly impaired, especially after ingestion of the strongest dose. The Cannabis Influence Factor (CIF) which relies on the molar ratio of active and inactive cannabinoids in blood provided a good estimate of the fitness to drive.
Comparable studies
Other randomized controlled trials on cannabis, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Cannabidiol inhibits THC-elicited paranoid symptoms and hippocampal-dependent memory impairment Healthy participants | 2012 | Randomized controlled trial | n = 48 |
| Distinct Effects of Δ9-Tetrahydrocannabinol and Cannabidiol on Neural Activation During Emotional Processing Healthy, English-native, right-handed men who had used cannabis 15 times or less in... | 2009 | Double-blind, randomized, placebo-controlled crossover trial | n = 15 |
| Acute Effects of a Single, Oral dose of d9-tetrahydrocannabinol (THC) and Cannabidiol (CBD) Administration in Healthy Volunteers Healthy male subjects | 2012 | Randomized controlled trial | n = 16 |
| Modulation of Mediotemporal and Ventrostriatal Function in Humans by Δ9-Tetrahydrocannabinol Healthy, native English-speaking, right-handed men of white race/ethnicity who had used... | 2009 | Randomized controlled trial | n = 15 |
| Cannabidiol (CBD) content in vaporized cannabis does not prevent tetrahydrocannabinol (THC)-induced impairment of driving and cognition Healthy volunteers with a history of light cannabis use | 2019 | Randomized, double-blind, within-subjects crossover | n = 14 |
Citations in the library
Cited by 2
Cites 5
- Assessment of Driving Capability Through the Use of Clinical and Psychomotor Tests in Relation to Blood Cannabinoids Levels Following Oral Administration of 20 mg Dronabinol or of a Cannabis Decoction Made with 20 or 60 mg Δ9-THC* Journal of Analytical Toxicology July 1, 2005
- Two cases of "cannabis acute psychosis" following the administration of oral cannabis BMC Psychiatry December 1, 2005
- A role for cannabinoid CB1 receptors in mood and anxiety disorders. Behavioural Pharmacology September 2005
- The psychotomimetic effects of intravenous delta-9-tetrahydrocannabinol in healthy individuals: implications for psychosis. Neuropsychopharmacology August 2004
- Action of cannabidiol on the anxiety and other effects produced by delta 9-THC in normal subjects. Psychopharmacology 1982