Definitions/Description

• Psilocybin (a classic psychedelic or referred to as just a psychedelic in the narrow sense of the term) and MDMA (an entactogen also sometimes referred to as a psychedelic, when the term is used in the broad sense) are currently the most studied and discussed psychedelic-type substances in medical research settings. In addition to psilocybin and MDMA, several other psychoactive substances produce altered states of consciousness and are being explored for therapeutic use. These psychedelics (in the broad sense of the term) include:
• 2C-B (2,5-dimethoxy-4-bromophenethylamine)
• 5-MeO-DMT (5-methoxy-N,N-dimethyltryptamine)
• DMT (dimethyltryptamine)
• Ibogaine (a naturally occurring plant alkaloid from Tabernanthe iboga)
• LSD (lysergic acid diethylamide)
• Mescaline (from peyote and San Pedro cacti)

These compounds vary in pharmacology and risk/benefit profiles, but all produce acute intensely altered states of consciousness (with changes in perception, affect, and cognition) with the possibility of persisting effects, especially to mood. None of these compounds are approved as medications and have different levels of evidence at present.