| Journal | Drug and alcohol dependence |
| Study Type | Randomized Trial |
| Population | Human participants |
This study provides critical pharmacokinetic data on CBD’s interaction with THC in vaporized cannabis, addressing a fundamental question about how these cannabinoids influence each other’s absorption and metabolism. Understanding these interactions is essential for dosing precision and predicting clinical effects in cannabis medicine.
This randomized, double-blind, crossover trial examined plasma cannabinoid levels in 35 participants (ages 16-17 and 26-29) after vaporizing weight-adjusted doses of THC alone (8mg/75kg), THC+CBD (8mg THC + 24mg CBD/75kg), or placebo. Blood samples were collected at baseline, 20, 30, and 160 minutes post-inhalation to analyze THC and metabolite concentrations. The study specifically investigated whether CBD co-administration alters THC pharmacokinetics and whether age modifies cannabinoid metabolism. The crossover design strengthens internal validity by having each participant serve as their own control across conditions.
“This fills an important knowledge gap about cannabinoid interactions that directly impacts how I counsel patients about combination products. The age comparison data is particularly valuable given the growing interest in cannabis medicine across age groups.”
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FAQ
Does CBD affect how THC is processed in the body when cannabis is vaporized?
This study examined whether CBD alters THC plasma concentrations when both compounds are inhaled together through vaporization. The research compared THC-alone versus THC+CBD preparations to determine if CBD influences THC pharmacokinetics, though the complete results are not provided in this summary.
The study specifically compared cannabinoid plasma pharmacokinetics between adolescents (16-17 years) and adults (26-29 years) using vaporized cannabis preparations. This research addresses an important clinical gap, as no prior studies have explored how age moderates cannabinoid pharmacokinetics following inhalation.
What dosages of THC and CBD were used in this clinical study?
The study used weight-adjusted dosing with 8mg THC per 75kg body weight for the THC-alone condition, and 8mg THC plus 24mg CBD per 75kg body weight for the combination condition. This represents a 3:1 CBD to THC ratio in the combination preparation, which is clinically relevant for understanding therapeutic cannabis formulations.
How quickly do THC levels peak in blood after vaporizing cannabis?
Blood samples were collected at 20, 30, and 160 minutes after inhalation began, indicating that peak plasma concentrations likely occur within the first 30 minutes. This timeframe is consistent with the rapid absorption characteristics of inhaled cannabis and is important for understanding onset of effects and dosing intervals.
Is this study design reliable for making clinical decisions about cannabis therapy?
This was a randomized, double-blind, placebo-controlled, crossover study with 48 participants, representing high-quality evidence design. The crossover design allows each participant to serve as their own control, reducing individual variability and strengthening the reliability of pharmacokinetic comparisons between different cannabis preparations.
