The CBD Cocaine Trial Timed Blood Sampling Around Daily Dosing
The trial measured CBD at specified times rather than treating any detected concentration as a complete adherence history. Collection timing matters when comparing those measurements.
The schedule had a deliberate exception
Daily inpatient treatment was administered at 10 a.m. Blood CBD measurements were scheduled at 9 a.m. on day eight and at outpatient weeks four and twelve. The day-nine measurement was at 1 p.m. The protocol therefore included samples taken at different nominal positions relative to the morning treatment schedule.
One concentration cannot establish every dose taken
The investigators also assessed outpatient adherence using medication volume in returned bottles. A bottle-volume estimate and a blood concentration supply different evidence. Neither alone proves that every prescribed dose was consumed at the instructed time. A later sample can differ because of timing as well as dose-taking behavior and pharmacokinetic variation.
Exposure and efficacy remain separate
The trial detected CBD exposure but did not demonstrate superiority over placebo for craving or relapse. Detecting active drug cannot override that outcome, and a single low measurement cannot automatically explain it. A review should retain scheduled and actual collection times, dose history and the relevant adherence method before attributing concentration differences to noncompliance.
Related analysis: the cocaine-craving and relapse findings.
Research cited
Mongeau-Pérusse and colleagues (2021). Cannabidiol as a treatment for craving and relapse in individuals with cocaine use disorder: a randomized placebo-controlled trial. DOI: 10.1111/add.15417.



