N,N-Dimethyltryptamine (DMT) is a naturally occurring hallucinogenic compound of the tryptamine family. DMT is found not only in several plants, but also in trace amounts in humans and other mammals, where it is originally derived from the essential amino acid tryptophan, and ultimately produced by the enzyme INMT during normal metabolism. The natural function of its widespread presence remains undetermined. Structurally, DMT is analogous to the neurotransmitter serotonin (5-HT), the hormone melatonin, and other psychedelic tryptamines, such as 5-MeO-DMT, bufotenin, and psilocin.
Many cultures, indigenous and modern, ingest DMT as a psychedelic drug, in either extracted or synthesized forms. When DMT is inhaled, depending on the dose, its subjective effects can range from short-lived milder psychedelic states to powerful immersive experiences, which include a total loss of connection to conventional reality, which may be so extreme that it becomes ineffable. DMT is also the primary psychoactive in ayahuasca, an Amazonian Amerindian brew employed for divinatory and healing purposes. Pharmacologically, ayahuasca combines DMT with an MAOI, an enzyme inhibitor that allows DMT to be orally active.
Similar to other psychedelic drugs, there are relatively few physical side effects associated with DMT acute exposure. When inhaled, its vapor has been described as "very harsh". According to a "Dose-response study of N,N-dimethyltryptamine in humans" by Rick Strassman, "Dimethyltryptamine dose slightly elevated blood pressure, heart rate, pupil diameter, and rectal temperature, in addition to elevating blood concentrations of beta-endorphin, corticotropin, cortisol, and prolactin. Growth hormone blood levels rose equally in response to all doses of DMT, and melatonin levels were unaffected." Psychologically, the DMT experience can be overly-intense, potentially causing overwhelming fear and difficulty integrating experiences, if one is not mentally prepared. Furthermore, due to the intense nature of the experience, DMT is generally considered to have no addiction potential.