Conclusions
PD, Δ9-THC
ADVERSE EFFECTS
In this randomized clinical trial, plasma exposure to Δ9-THC, 11-OH-Δ9-THC, and Δ9-THC-COOH following ingestion of Δ9-THC + CBD was greater than that following ingestion of Δ9-THC and placebo. Consequently, participants experienced greater increases in subjective drug effects, impairment of cognitive and psychomotor performance, and HR. With legalized medicinal and nonmedicinal use of cannabis continually expanding, cannabis users and clinical or regulatory stakeholders must understand that differential chemical compositions other than Δ9-THC can significantly alter the PK and PD of cannabis products. High concentrations of CBD can inhibit Δ9-THC metabolism, which can increase the likelihood of acute adverse effects compared with the same dose of Δ9-THC in the absence of CBD.