Psilocybin and psilocin, the main hallucinogenic compounds in magic mushrooms, act as agonists or partial agonists at 5-HT2A receptors. Psilocybin is a pro-drug dephosphorylated by alkaline phosphatase to the active metabolite psilocin, which is further metabolized; psilocin-O-glucuronide is the main urinary metabolite with clinical and forensic relevance. Considerable physiological variability between individuals influences dose-response and toxicological profiles. The review presents all major and minor psychoactive metabolites of psilocybin and psilocin.
Lysergic acid diethylamide (LSD), the most potent known hallucinogen, exerts its pharmacological effects by stimulating central serotonin receptors (5-HT2). Despite its low toxicity and physiological safety, renewed therapeutic interest has emerged. This review discusses LSD metabolism, detailing all metabolites and their clinical and toxicological relevance. LSD is rapidly and extensively metabolized into inactive metabolites, which have a longer detection window than the parent compound. The major human metabolite, 2-oxo-3-hydroxy LSD, is crucial for clinical and forensic toxicology. However, information on LSD pharmacokinetics in humans remains limited, highlighting the need for further research.