mescaline

Mescaline is a naturally occurring psychedelic alkaloid in the phenethylamine class. It is most famously found in the peyote cactus (Lophophora williamsii) and is also present in other cacti such as the San Pedro (Echinopsis pachanoi) and the Peruvian torch (Echinopsis peruviana).

Chemically, mescaline is 3,4,5-trimethoxyphenethylamine. It acts as a serotonin 2A receptor agonist and, at sufficient doses, produces profound alterations of perception, mood, and cognition, including vivid visual phenomena and changes in thought content. Effects typically begin within 1 to 2 hours after ingestion and may last 8 to 12 hours depending on dosage and setting.

History and ethnography: Mescaline was first isolated in 1897 by German pharmacologist Arthur Heffter from peyote. Indigenous peoples in Mexico and the southwestern United States have used peyote and mescaline-containing cacti in ceremonial contexts for centuries; the use remains a central practice in the Native American Church in some regions, governed by local laws.

Legal status and safety: Mescaline is a controlled substance in many countries; in the United States it is Schedule I under the Controlled Substances Act, with limited exemptions for certain Native American religious use. Adverse effects can include nausea, vomiting, anxiety, paranoia, or psychotic-like experiences, particularly in vulnerable individuals or in uncontrolled environments. There is no established medical use in many jurisdictions, and it should not be used without appropriate oversight.