Men and women experienced largely similar acute effects after smoking marijuana across THC potencies ranging from 6.25% to 22%, according to a new placebo-controlled study published in Psychopharmacology. The study used a randomized, double-blind, placebo-controlled, within-subject design, allowing researchers to compare physiological effects, blood and oral-fluid cannabinoid concentrations, subjective effects, mood and cognitive performance after each potency. Females and males smoked similar amounts of marijuana and reached similar concentrations of THC and its metabolites in their blood. However, females spent significantly more time smoking and had significantly lower THC concentrations in oral fluid. Differences in smoking patterns and other physiological factors could therefore influence oral-fluid THC levels even when blood THC concentrations are similar.