Science

For many Indigenous peoples, ayahuasca and other teacher plants are not a substance but part of a complex system of knowledge: a medicine, a way of learning and of relating to the land and to the sacred. Recognising that knowledge, and those who safeguard it, is part of the FERM Code of Ethics.

Integration is the work of making sense of what was lived through in an experience with entheogens and carrying it into everyday life, and of asking for help when an experience proves difficult. A leading figure in this field is the psychologist Marc Aixalà, who for years coordinated the ICEERS integration service.

Field and observational studies with ayahuasca consistently find lower use of alcohol and other drugs. Controlled clinical trials with ayahuasca are still lacking; with other entheogens, such as psilocybin, they already exist and point in the same direction.

Much of what is known about how ayahuasca acts in the human body was researched in Barcelona, at the Hospital de Sant Pau, led by Jordi Riba (1968–2020). His work, continued by José Carlos Bouso and ICEERS, laid the foundations of the clinical pharmacology of ayahuasca.

Psilocybin, the active compound in psilocybin mushrooms, is the entheogen with the most clinical trials. Other studies with psilocybin appear under Mental health and Addiction. The results are promising, but most trials are small and double-blinding is hard to maintain.

Iboga is a sacred shrub of the Bwiti tradition of Gabon; ibogaine is its main alkaloid. It is studied above all in opioid addiction, but the evidence is observational and its cardiac risk is well documented: it prolongs the QT interval, can cause serious arrhythmias and deaths have been recorded. It requires medical assessment and cardiac monitoring.

Mescaline is found in traditionally used cacti such as peyote, sacred to the Native American Church, and San Pedro or huachuma from the Andes. Clinical evidence is scarce: surveys, one study with ritual users and pharmacology trials with healthy volunteers. Peyote is also a threatened species.

5-MeO-DMT produces extremely intense, almost immediate effects. It is obtained from the secretion of the Incilius alvarius toad or by synthesis. Its use has grown on the back of false accounts of ancestral Indigenous use, and the pressure on the toad poses a conservation problem.

Salvia divinorum, a plant traditionally used by the Mazatec people of Mexico, acts through a different pathway from the classic psychedelics. The two most-cited studies in humans were carried out in Barcelona.