Duration

Duration is the total period over which perceptible cannabis effects persist after administration. It reflects the integrated pharmacokinetic/pharmacodynamic time course — how long plasma and brain THC plus active 11-OH-THC remain above the threshold for measurable CNS effect. Inhaled cannabis produces subjective effects lasting ~2–4 hours, tapering rapidly despite much longer detectable plasma levels (Grotenhermen 2003; Spindle 2018). Oral/edible cannabis lasts 4–12 hours, occasionally longer at high doses, because slower absorption, enterohepatic recirculation, and substantial 11-OH-THC exposure prolong the pharmacodynamic window (Vandrey 2017; Newmeyer 2017). Critically, the terminal elimination half-life of THC (~20–30 h) and THC-COOH (days to weeks) greatly exceeds subjective duration — biological detection windows persist far beyond perceived effects. Tolerance, dose, co-administered CBD, and prior use pattern modulate duration. Citations: Grotenhermen F. Clin Pharmacokinet. 2003;42:327-360; Newmeyer MN et al. Clin Chem. 2017;63:647-662; Spindle TR et al. JAMA Netw Open. 2018;1(7):e184841.