Rumination is a well-established risk factor for the onset and maintenance of depression and anxiety and has been identified as a transdiagnostic factor due to its association with multiple forms of psychopathology. A renaissance of psychedelic research shows promise in treating psychopathology with potential for acting on ruminative processes. Despite the growing interest and developments in legality, very few research studies have investigated the psychological consequences of participating in an ayahuasca ceremony in North America. The current study included 30 participants (Mage = 41.03, SD = 7.35; range = 30-59 years; 50.0% women; 76.7% White/Caucasian) who participated in an ayahuasca ceremony at a North American ayahuasca church. Participants were asked to complete seven daily surveys prior to their ceremony (Phase I) and seven daily surveys following their ceremony (Phase II). Multi-level models tested changes in rumination and depression, anxiety, and stress scores across both phases of the study. Significant and large reduction were evidenced in levels of rumination and depression, anxiety, and stress immediately following the ayahuasca ceremony. This effect was maintained during Phase II, with scores remaining lower than Phase I and relatively stable. Furthermore, path models did not support the mediating role of rumination in the negative link between ayahuasca ceremony effects (as indexed via ego-dissolution) and depression, anxiety, and stress scores (though evidence for mediation was found without bootstrapping samples). Findings of this study contribute to the emerging literature on the role that ceremonial ayahuasca use may have on reducing psychological distress.