After first-time ritual use of ayahuasca in the Santo Daime and União do Vegetal religious groups, participants reported predominantly positive expectations beforehand. The most salient altered-state experiences included visual phenomena, a sense of the numinous, peacefulness, insights, and some distressing reactions. In the Santo Daime group, minor psychiatric symptoms significantly reduced. Both groups reported behavioral changes toward assertiveness, serenity, and vivacity or joy. Findings are discussed in terms of set and setting, suggestibility, and ayahuasca's unique effects.
Twenty-three people were assessed just before and six months after their first ayahuasca experience in two Brazilian religious groups. In the Santo Daime group, minor psychiatric symptoms decreased, mental health improved, and attitudes shifted toward greater confidence and optimism. In the União do Vegetal group, physical pain decreased and attitudes shifted toward greater independence. More frequent ayahuasca use was linked to more independence, while a longer period without ayahuasca was linked to less independence. The authors discuss possible mechanisms behind these changes and suggest areas for future research.