Pharmacokinetics and subjective effects of 1P-LSD in humans after oral and intravenous administration.
1-Propanoyl-lysergic acid diethylamide (1P-LSD) appeared as a non-controlled alternative to LSD a few years ago. Although evidence is beginning to emerge from in vitro and animal studies that 1P-LSD might serve as a prodrug for LSD, an equivalent evaluation in humans is unavailable. Controlled oral and intravenous self-administrations of 100 μg 1P-LSD hemitartrate are reported in two human volunteers followed by analyses of urine and serum samples using a fully validated LC-MSMS method. Psychometric evaluations included assessment of selected subjective drug effects and administration of the Five-Dimensions of Altered States of Consciousness rating scale (5D-ASC). In serum and urine, oral administrations of 1P-LSD only led to the detection of LSD reflecting biphasic elimination with a terminal elimination half-life of approx. t