Michelle Muscat MD MRCS(Ed) MSc, PG Dip, FRCPath, PhD

The naturally occurring psychedelic mescaline has been around for a very long time (1). It is part of the family of compounds collectively termed phenethylamines. The alkaloid is mostly, but not exclusively, obtained from the Peyote and San Pedro cacti. Ancient ceremonies (2) regarded the cactus as sacred. It is potentially hallucinogenic (3, 4) and thought to enhance introspective states. Intoxication alters perceptions and feelings, having the potential to induce euphoria and altered consciousness states. Cassels and Saez-Briones described it as a ‘dark classic in chemical neuroscience’ (5). Notably Aldous Huxley authored ‘The Doors of Perception’, which details his mescaline experience. ‘Crystal Fairy & The Magical Cactus’ is a movie that centers on the quest for the mescaline experience derived from the San Pedro cactus. Experiments were conducted in the past on mescaline intoxicated human subjects (6). Havelock Ellis described … a ‘saturnalia of the senses’.

Effects include behavioral disinhibition (7), nervousness, tachycardia, hallucinations, paranoia and mydriasis. Carstairs et al. did not report life threatening toxicity (8) in a case series of mescaline intoxications mined from a poison center database. Some other potential side-effects of the drug include dizziness, headaches, profuse sweating, nausea, vomiting, accidental injuries and hallucinogen persisting perception disorder. It is thought addiction and dependence are highly unlikely (9), however tolerance may occur with repeat usage. An isolated report of a mescaline related death is presented by Reynolds et al. (10). There has also been synthesis of mescaline analogues (11). Validated laboratory methods (12, 13) are used to detect mescaline. This drug has been tested on rats with respect to memory and learning (14) and it accelerated memory decay (15). Rats showed motor impairment on mescaline (16).


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