A systematic review of 13 publications covering eight datasets found that the pharmacokinetics of DMT in humans have been characterized only to a limited extent. All studies administered DMT intravenously except one intramuscular injection. DMT is rapidly metabolized to indole-3-acetic acid (IAA), with a half-life of 4.8–19.0 minutes and clearance of 8.1–46.8 L/min. It shows extensive tissue redistribution, indicated by a high terminal volume of distribution (123–1084 L). High variability in dose-normalized exposure and differences between bolus and infusion administration were observed. Publications often lack details on demographics, absolute doses, and pharmacokinetic parameters, highlighting the need for further studies.
Mescaline, a classic psychedelic, shows dose-proportional increases in blood concentration and effects after oral administration. Peak levels occur within about 2 hours, with a half-life of 3.5 hours. Effects begin around 1 hour after dosing, with intensity and duration increasing from 13% and 2.8 hours at 100 mg to 89% and 15 hours at 800 mg. About 53% of the dose is excreted unchanged in urine, and 31% as a main metabolite. Oral bioavailability is at least 53%, limited by first-pass metabolism, with renal elimination as the primary clearance route.