Ayahuasca-Induced Serotonin Syndrome: Risks, Mechanisms, and Clinical Considerations

Ayahuasca, a traditional Amazonian brew combining Banisteriopsis caapi and Psychotria viridis, produces psychedelic effects through a synergistic pharmacological action: β-carbolines (harmine, tetrahydroharmine, and harmaline) inhibit monoamine oxidase A, allowing N,N-dimethyltryptamine (DMT) to reach active levels in the central nervous system and act as a serotonergic agonist at 5-HT2A, 5-HT2C, and 5-HT1A receptors. Preclinical studies and early clinical trials suggest antidepressant, anxiolytic, anti-inflammatory, and neuroplastic benefits, with no evidence of dependence or significant tolerance. Risks include psychotic episodes, hazardous interactions with SSRIs, potential serotonin syndrome, nausea, vomiting, and cardiovascular changes. The authors argue that controlled clinical research is essential to establish safety, efficacy, and toxicological profile.

Study at a glance

Abstract

Ayahuasca is a traditional Amazonian brew composed primarily of Banisteriopsis caapi and Psychotria viridis, drawing increasing interest for its psychedelic effects and potential therapeutic applications. Its pharmacological action is based on the synergistic combination of β-carbolines (harmine, tetrahydroharmine, and harmaline), which act as reversible inhibitors of monoamine oxidase A (MAO-A), and N,N-dimethyltryptamine (DMT), a serotonergic agonist at 5-HT2A, 5-HT2C, and 5-HT1A receptors. This interaction enables DMT to reach active levels in the central nervous system by preventing gastrointestinal degradation. Preclinical studies and early clinical trials suggest antidepressant, anxiolytic, anti-inflammatory, and neuroplastic benefits, with no evidence of dependence or significant tolerance. Nonetheless, risks remain, including psychotic episodes, hazardous interactions with SSRIs, and the potential for serotonin syndrome. Adverse events such as nausea, vomiting, and cardiovascular changes must be considered. Although the current data are promising, controlled clinical research is essential to establish the safety, efficacy, and toxicological profile of ayahuasca in therapeutic contexts.