Cannabis edibles produced delayed, lower blood THC peaks than smoking, with women showing higher concentrations

After consuming cannabis brownies (0, 10, 25, or 50 mg THC), blood THC and 11-OH-THC peaked at 1.5-2 hours and returned to baseline within 8 hours. THCCOOH and THCCOOH-glucuronide were higher than THC and persisted beyond 8 hours. Women had higher peak THC and metabolite concentrations, partly due to lower body weight/BMI. Oral fluid THC was detected immediately (oral deposition, not blood circulation) and was much higher than blood THC.

Randomized, double-blind, 4-session study in 17 healthy adults (8 female, no cannabis for 60+ days) consuming 0, 10, 25, or 50 mg THC brownies. Blood and oral fluid collected for 8 hours; analyzed by ELISA and LC-MS/MS.

This is one of the few controlled studies with both sexes examining oral cannabis pharmacokinetics. The sex differences (higher THC in women) and oral fluid findings (immediate detection not reflecting blood levels) have direct implications for drug testing interpretation.

Roadside oral fluid testing for cannabis may detect oral deposition from eating edibles, not actual impairment. The immediate oral fluid detection following edibles (before blood levels rise) means a positive oral fluid test does not confirm systemic THC exposure.

Small sample (17, 8 female); infrequent users only; single edible form (brownie); 8-hour window may not capture full duration of higher doses; no direct impairment measurements alongside PK; body weight/BMI only partially explains sex differences.