Psilocybin, a prodrug found in magic mushrooms, is converted in the body to psilocin, the compound responsible for cognitive effects. Existing methods to measure psilocin in plasma, serum, or urine may yield misleading pharmacokinetic data because the blood-to-plasma ratio is unknown. This work developed the first analytical method using solid-phase extraction and liquid chromatography–tandem mass spectrometry to quantify psilocin in human whole blood. The procedure achieved high recovery (≥89%) with minimal matrix effects, validated per ANSI/ASB 036 guidelines. Linearity ranged from 0.7 to 200 ng/mL, covering previously reported plasma levels. Psilocin was stable at 4°C for 48 hours. The method successfully detected and quantified psilocin at low limits in whole blood, though a proof-of-concept study is still needed.
Ayahuasca's primary psychedelic alkaloid, N,N-dimethyltryptamine (DMT), is rapidly metabolized: oxidative deamination yields indole-3-acetic acid (IAA) as the main metabolite, and N-oxidation produces N,N-dimethyltryptamine-N-oxide (DMT-NO) as the second most abundant. A validated LC-MS/MS method quantified DMT, IAA, and DMT-NO in human plasma and DMT and DMT-NO in urine with high recovery (≥91%), low bias (±17.5%), and good precision (≤6.4%). In a proof-of-concept study using paired blood and urine samples, DMT and DMT-NO concentrations were higher in urine than plasma, reflecting rapid clearance. DMT and DMT-NO are proposed as direct biomarkers for exogenous DMT consumption; IAA should not be the sole biomarker due to its substantial endogenous presence.