Ayahuasca, a traditional beverage, contains monoamine oxidase inhibitors (harmine, harmaline, tetrahydroharmine) and N,N-dimethyltryptamine (DMT), which produces visionary effects. Analysis of nine ayahuasca aqueous extracts and three seized powder samples using HPLC-DAD revealed DMT concentrations of 402–2070.3 μg/mL, harmaline 27.5–181.3 μg/mL, harmine 294.5–2893.8 μg/mL, and tetrahydroharmine 849.5–2052.5 μg/mL in the extracts. One powder sample contained only DMT (82% and 2% w/w), another only harmaline (16% w/w) and harmine (12% w/w). Ritual oral ayahuasca use reduces overdose risk via vagal stimulation causing vomiting, whereas recreational smoking or inhalation of DMT increases bioavailability and intoxication potential.
Ayahuasca tea has been used for millennia by indigenous peoples of South America as a spiritual and ritual instrument with extreme religiosity. In the last century, non-indigenous sects began using the tea, and this use has increased since its legalization for religious purposes in Brazil. The tea's action is due to alkaloids in the plants used in its preparation: the vine Banisteriopsis caapi and the leaves of the shrub Psychotria viridis. Observed effects include hallucinations, hypertension, tachycardia, nausea, vomiting, and diarrhea. These actions can cause more serious effects on the body and thus deserve greater attention from health professionals to promote studies that allow religious use without greater biological harm and to raise user awareness of possible toxic effects.