Driving under the influence of cocaine and MDMA: Relationship between blood concentrations and results from clinical test of impairment.
Gunhild Heide, Ragnhild Elén Gjulem Jamt, Jonas Fainberg-Sandbu, Åse Marit Leere Øiestad, Gudrun Høiseth
Journal of Analytical Toxicology June 11, 2024 DOI: 10.1093/jat/bkae024 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Observational cohort Peer reviewed |
|---|---|
| Sample size | 4,900 |
| Population | Apprehended drivers in Norway, 2000-2022 |
| Duration | 2000-2022 |
| Topics | MDMA |
| Keywords | Drug testing Impaired driving Traffic safety Substance abuse |
| Citations | 8 |
| Key findings | Higher blood cocaine concentration was associated with increased odds of clinical impairment, but no such relationship was found for MDMA. |
Abstract
The general use of cocaine is increasing in recent years, while the trend for 3,4-methylenedioxymethamphetamine (MDMA) is less clear. The relationship between blood concentrations and impairment is poorly understood, which complicates interpretation. The aims of this study were to report prevalence and blood concentrations of cocaine and MDMA in drugged drivers, and to investigate the relationship between blood concentrations and impairment. Samples of whole blood were collected from apprehended drivers in the period 2000-2022, and a clinical test of impairment (CTI) was simultaneously performed. The samples were initially analyzed for cocaine and MDMA using gas chromatography-mass spectrometry (until 2009 and 2012, respectively), and later using ultra-high-performance liquid chromatography-tandem mass spectrometry. Overall, cocaine was detected in 2,331 cases and MDMA in 2,569 cases. There were 377 and 85 mono cases of cocaine and MDMA, respectively. In the mono cases, the median cocaine concentration was 0.09 mg/L (range: 0.02-1.15 mg/L), and 54% of the drivers were clinically impaired. The median MDMA concentration was 0.19 mg/L (range: 0.04-1.36 mg/L), and 38% were clinically impaired. There was a statistically significant difference in the median cocaine concentration between drivers assessed as not impaired (0.07 mg/L) and drivers assessed as impaired (0.10 mg/L) (P = 0.009). There was also a significant effect of the blood concentration of cocaine (adjusted odds ratio [aOR] = 6.42, 95% confidence interval [CI] = 1.13-36.53, P = 0.036) and driving during the evening/night-time (aOR = 2.17, 95% CI = 1.34-3.51, P = 0.002) on the probability of being assessed as impaired on the CTI. No significant differences were found for MDMA. Many drivers are not assessed as impaired on a CTI following cocaine or especially MDMA use. For cocaine, a relationship between blood concentrations and impairment was demonstrated, but this could not be shown for MDMA.
Comparable studies
Other observational and cohort studies on MDMA, most cited first.
| Study | Year | Design | Participants |
|---|---|---|---|
| Subjective Reports of the Effects of MDMA in a Clinical Setting Individuals who took MDMA in a clinical setting | 1986 | Observational study | |
| Memory impairment in abstinent MDMA ("Ecstasy") users Abstinent MDMA users | 1998 | Observational cohort | |
| Impaired cognitive performance in drug free users of recreational ecstasy (MDMA) Otherwise healthy young people | 2000 | Observational | |
| The Psychological and Physiological Effects of MDMA on Normal Volunteers Older, more educated, drug-experienced individuals | 1986 | Observational cohort | |
| Cognitive performance in recreational users of MDMA or 'ecstasy': evidence for memory deficits Young people who were regular or novice MDMA users, or non-users | 1998 | Observational cohort | n = 30 |
Citations in the library
Cited by 3
- Trends in toxicological findings and drug seizures of MDMA in New Zealand from 2010 to 2022 Journal of Forensic Sciences February 12, 2026
- Possible Effects of MDMA on Vehicle Driving Competencies Transportation research procedia 2026
- Review of Selected 2-Phenylethylamine Derivatives and Opioids, Systematic Review of Their Effects on Psychomotor Abilities and Driving Performance: Psychopharmacology in the Context of Road Safety Pharmaceuticals October 28, 2025
Cites 8
- Human Pharmacology of MDMA Therapeutic Drug Monitoring March 19, 2004
- Human psychopharmacology of Ecstasy (MDMA): a review of 15 years of empirical research Human Psychopharmacology: Clinical and Experimental December 1, 2001
- Human Pharmacology of 3,4-Methylenedioxymeth-amphetamine ("Ecstasy"): Psychomotor Performance and Subjective Effects Journal of Clinical Psychopharmacology August 1, 2000
- Dissociable Effects of a Single Dose of Ecstasy (MDMA) on Psychomotor Skills and Attentional Performance Journal of Psychopharmacology December 1, 2003
- Stimulant effects of 3,4‐methylenedioxymethamphetamine (MDMA) 75 mg and methylphenidate 20 mg on actual driving during intoxication and withdrawal Addiction August 8, 2006
and 3 more in the library