4.3. Ayahuasca
Ayahuasca is a psychoactive substance, usually ingested as a beverage, decocted from Banisteriopsis caapi and Psychotria viridisplants. They are rich in DMT, a partial 5-HT serotonergic receptor agonist and have direct monoamine-oxidase A (MAO-A) inhibiting properties. Through both mechanisms, ayahuasca has psychedelic effects.84 Ayahuasca has been historically and culturally used by those in several countries in Central and South America, however, it has recently been more widely used, particularly in religious and spiritual contexts.85
So far, no studies have investigated the role of ayahuasca in the management of pain as a primary outcome. One recent study included the Medical Outcomes Study 36-Item Short-Form (SF-36) as a secondary measurement including a subcomponent rating of participant’s bodily pain.86 In this report, the authors conducted two observational sub-studies: (1) one with first-time ayahuasca users (n = 40), and (2) adding a comparison group of long-term ayahuasca users (n = 23). Reported improvements in depression rates for first-time ayahuasca users and lower depression scores among long-term ayahuasca users were found. However, there were no significant changes in bodily pain for first-time ayahuasca users. In a similar study with 23 first-time ayahuasca users showed similar findings but with significant reductions in the bodily pain component of the SF-36 for a subgroup of participants (n = 8).87 Despite the mechanistic plausibility of ayahuasca for pain treatment given its serotonergic and other relevant mechanisms of action, the literature on the topic is underdeveloped and the little available evidence is conflicting.