Journal article
Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol
Clinical chemistry (Baltimore, Md.), Vol.61(6), pp.850-869
06/2015
DOI: 10.1373/clinchem.2015.238287
PMID: 26019183
Abstract
Increased medical and legal cannabis intake is accompanied by greater use of cannabis vaporization and more cases of driving under the influence of cannabis. Although simultaneous Δ(9)-tetrahydrocannabinol (THC) and alcohol use is frequent, potential pharmacokinetic interactions are poorly understood. Here we studied blood and plasma vaporized cannabinoid disposition, with and without simultaneous oral low-dose alcohol.
Thirty-two adult cannabis smokers (≥1 time/3 months, ≤3 days/week) drank placebo or low-dose alcohol (target approximately 0.065% peak breath-alcohol concentration) 10 min before inhaling 500 mg placebo, low-dose (2.9%) THC, or high-dose (6.7%) THC vaporized cannabis (6 within-individual alcohol-cannabis combinations). Blood and plasma were obtained before and up to 8.3 h after ingestion.
Nineteen participants completed all sessions. Median (range) maximum blood concentrations (Cmax) for low and high THC doses (no alcohol) were 32.7 (11.4-66.2) and 42.2 (15.2-137) μg/L THC, respectively, and 2.8 (0-9.1) and 5.0 (0-14.2) μg/L 11-OH-THC. With alcohol, low and high dose Cmax values were 35.3 (13.0-71.4) and 67.5 (18.1-210) μg/L THC and 3.7 (1.4-6.0) and 6.0 (0-23.3) μg/L 11-OH-THC, significantly higher than without alcohol. With a THC detection cutoff of ≥1 μg/L, ≥16.7% of participants remained positive 8.3 h postdose, whereas ≤21.1% were positive by 2.3 h with a cutoff of ≥5 μg/L.
Vaporization is an effective THC delivery route. The significantly higher blood THC and 11-OH-THC Cmax values with alcohol possibly explain increased performance impairment observed from cannabis-alcohol combinations. Chosen driving-related THC cutoffs should be considered carefully to best reflect performance impairment windows. Our results will help facilitate forensic interpretation and inform the debate on drugged driving legislation.
Details
- Title: Subtitle
- Controlled Cannabis Vaporizer Administration: Blood and Plasma Cannabinoids with and without Alcohol
- Creators
- Rebecca L HartmanTimothy L Brown - University of IowaGary Milavetz - University of IowaAndrew Spurgin - University of IowaDavid A Gorelick - University of Maryland, BaltimoreGary Gaffney - Roy J. and Lucille A. Carver College of MedicineMarilyn A Huestis - National Institute on Drug Abuse
- Resource Type
- Journal article
- Publication Details
- Clinical chemistry (Baltimore, Md.), Vol.61(6), pp.850-869
- DOI
- 10.1373/clinchem.2015.238287
- PMID
- 26019183
- NLM abbreviation
- Clin Chem
- ISSN
- 0009-9147
- eISSN
- 1530-8561
- Grant note
- Intramural NIH HHS
- Language
- English
- Date published
- 06/2015
- Academic Unit
- Pharmacy; Psychiatry; Pharmaceutical Sciences and Experimental Therapeutics; Pharmacy Practice and Science; Injury Prevention Research Center
- Record Identifier
- 9984365894902771
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