A press-release from The International Center for Ethnobotanical Education, Research & Service (ICEERS) states that there is no evidence of adverse psychiatric or neuropsychological effects found in study of long-term ayahuasca users.
The study, published by the scientific journal PLOS ONE, found no association between the long-term use of ayahuasca in a religious context and any mental health deficits. The ayahuasca users had higher scores in cognitive tests and lower psychopathological indices compared with the control group. The study was conducted by the Human Experimental Neuropsychopharmacology group of Hospital Sant Pau, in collaboration with researchers from several Spanish and Brazilian research centers and the Institute for Applied Amazonian Ethnopsychology (IDEAA)
The Spanish and Brazilian research team evaluated several domains of mental health in 127 ayahuasca users in religious contexts who had been drinking ayahuasca at least twice a month for at least 15 years. They compared these participants with 115 non-users. To confirm the reliability of the results, they repeated the tests one year later. The ayahuasca users showed no personality disorders, and had lower psychopathological indices and better cognitive performance in neuropsychological tests than the non-users. The study concludes that there is “no evidence of psychological maladjustment, mental health deterioration or cognitive impairment in the ayahuasca-using group.” These results are consistent with earlier results obtained by other research groups that had studied smaller samples of users. This is the first study with long-term ayahuasca users that both assessed a sample of this size and replicated the results.
Read the full press release here.