A liquid chromatography–tandem mass spectrometry method was developed to measure LSD and its isomer iso-LSD in blood or urine, with a detection limit of 0.02 micrograms per liter. Applied to two real cases, LSD concentrations ranged from 0.24 to 1.30 micrograms per liter. The main metabolite identified in urine was 2-oxo-3-hydroxy-LSD at 2.5 and 6.6 micrograms per liter, which was absent in plasma. Additional metabolites including nor-LSD, lysergic acid ethylamide, and various hydroxylated and glucuronide-conjugated forms were detected using specific mass spectrometry transitions.
2C-P is a hallucinogenic designer drug from the phenethylamine class. This work identified its phase I and II metabolites and tested detectability in urine. Proposed metabolic pathways include N-acetylation, deamination with reduction to alcohol or oxidation to carbonic acid, mono- and bis-hydroxylation, mono- and bis-O-demethylation followed by glucuronidation or sulfation, and combinations. A common user's dose of 2C-P was reliably detectable in urine using standard GC-MS and LC-MS(n) screening methods, supporting its identification in clinical and forensic cases.