University of Wisconsin researchers gave healthy volunteers increasing monthly doses of psilocybin and took blood and urine samples over a 24-hour period after each dose. They report in Clinical Pharmacokinetics they found no psilocybin in plasma or urine and unmetabolized psilocybin accounted for <2% of the total clearance. Also, “The pharmacokinetics of psilocin were linear within the twofold range of doses, and the elimination half-life of psilocin was 3 h.” Finally, “Simulation of fixed doses using the pharmacokinetic parameters suggest that an oral dose of 25 mg should approximate the drug exposure of a 0.3 mg/kg oral dose of psilocybin.”