Dimethyltryptamine (DMT), also known as N,N-dimethyltryptamine, (not to be confused with 5-MeO-DMT), is a psychedelic coumpound . DMT is closely related to serotonin, the naturally occurring neurotransmitter that psychedelics affect so widely. DMT is created in small amounts by the human body during normal metabolism by the enzyme Tryptamine-N-methyltransferase.
DMT is present in over 65 species of plants and has been identified as being a normal constituent of human metabolism and an endogenous neurotransmitter in certain rodents. Its presence is also known to be widespread throughout the plant kingdom.
Unlike most highly prohibited substances, DMT is not considered to be addictive or toxic by the scientific community. Nevertheless, unpredictable adverse reactions such as uncontrollable anxiety, delusions and psychosis can always occur, particularly among those predisposed to mental disorders. While these negative reactions or “bad trips” can often be attributed to user inexperience or improper preparation of set and setting, they have been known to happen spontaneously among even highly experienced users as well. It is therefore highly advised to use harm reduction practices if using this substance.
Psychedelic alchemist Alexander Shulgin devotes an entire chapter to DMT in TIHKAL: Tryptamines I Have Known and Loved. He aptly entitles this chapter “DMT Is Everywhere” and declares: “DMT is . . . in this flower here, in that tree over there, and in yonder animal. [It] is, most simply, almost everywhere you choose to look.” Indeed, it is getting to the point where one should report where DMT is not found, rather than where it is.
The artificial compound DMT was not thought to be of particular pharmacological interest, until 24 years after its discovery it was determined to be a natural product and possible active principle of a well-known entheogenic snuff. The synthetic natural DMT produced in Szara’s laboratory proved to be powerfully visionary and “so short acting, it is over before you realize it happens,” with an unusually rapid onset, merely two to three minutes following intramuscular injection. 
Early in 1961, the American writer and drug experimentalistWilliam Burroughs began self-experiments with DMT, in doses of around 65 mg, “with results sometimes unpleasant but well under control and always interesting” until he inadvertently took an “overdose” of about lOO mg which precipitated a “horrible experience,” following which Butroughs “sounded a word of urgent warning” to other experimenters. In spite of Burroughs’ warnings, Timothy Leary and Ralph Metzner, then of Harvard University, decided to try DMT with controlled set and appropriate setting, and in the premier issue of The Psychedelic Review, in 1963, Metzner reported that DMT was “in doses of 1 mg/kg, similar to LSD or mescaline, but with a shorter duration of effect”. Although religious philosopher Alan Watts dismissed DMT as “amusing but relatively uninteresting”, Leary called it “this wondrous alkaloid” and commented “in 25 minutes (about the duration of the average sermon) you are whirled through the energy dance, the cosmic process, at the highest psychedelic speed. The 25 minutes are sensed as lasting for a second and for a billion year Kalpa” 
DMT’s psychedelic effects are believed to come from its efficacy at the 5-HT2A receptor as a partial agonist. However, the role of these interactions and how they result in the psychedelic experience continues to remain elusive. In addition to this, N,N-dimethyltryptamine is believed to be an endogenous ligand for the sigma receptor. However, the significance of the sigma-1 receptor remains the subject of ongoing scientific research.
Depending on the dosage and method of administration, the effects of DMT can range from mild psychedelic states to powerfully immersive life-altering experiences which are often described as the ultimate displacement from ordinary consciousness in which users report experiencing ineffable spiritual realms or alternate dimensions.
When vaporized or smoked, DMT produces short-lived effects with a very rapid onset that is sometimes described as an “inconceivably high-speed rollercoaster ride.” When ingested in combination with a MAOI or RIMA agent, it becomes active orally and significantly longer lasting, immersive, and interactive in nature: this combination is known as ayahuasca. Ayahuasca brews have been used traditionally in South America for millennia.
Human Body V.S. DMT
In his book “The Spirit Molecule”  Dr. Rick Strassman postulates :
“DMT is closely related to serotonin, the neurotransmitter that psychedelics affect so widely. The pharmacology of DMT is similar to that of other well-known psychedelics. It affects receptor sites for serotonin in much the same way that LSD, psilocybin, and mescaline do. These serotonin receptors are widespread throughout the body and can be found in blood vessels, muscle, glands, and skin. However, the brain is where DMT exerts its most interesting effects. There, sites rich in these DMT-sensitive serotonin receptors are involved in mood, perception, and thought. Although the brain denies access to most drugs and chemicals, it takes a particular and remarkable fancy to DMT. It is not stretching the truth to suggest that the brain “hungers” for it. The brain is a highly sensitive organ, especially susceptible to toxins and metabolic imbalances. A nearly impenetrable shield, the blood-brain barrier, prevents unwelcome agents from leaving the blood and crossing the capillary walls into the brain tissue. This defense extends even to keeping out the complex carbohydrates and fats that other tissues use for energy. The brain burns instead only the purest form of fuel: simple sugar, or glucose.
Twenty-five years ago, Japanese scientists discovered that the brain actively transports DMT across the blood-brain barrier into its tissues. I know of no other psychedelic drug that the brain treats with such eagerness. Once the body produces or takes in DMT, certain enzymes break it down within seconds. These enzymes, called monoamine oxidases (MAO), occur in high concentrations in the blood, liver, stomach, brain, and intestines. The widespread presence of MAO is why DMT effects are so short-lived. In a way, DMT is “brain food,” treated in a manner similar to how the brain handles glucose, its precious fuel source. It is part of a “high turn- over” system: quick in, quick used. The brain actively transports DMT across its defense system and just as rapidly breaks it down. It is as if DMT is necessary for maintaining normal brain function. It is only when levels get too high for “normal” function that we start undergoing unusual experiences.”
. Barker SA, Monti JA and Christian ST (1981). N,N-Dimethyltryptamine: An endogenous hallucinogen. In International Review of Neurobiology, vol 22, pp. 83-110; Academic Press, Inc. . Ott, Jonathan (1994). Ayahuasca Analogues: Pangæan Entheogens (1st ed.). Kennewick, WA, USA: Natural Products. pp. 81–83. ISBN 978-0-9614234-5-2. . Shulgin, Alexander; Shulgin, Ann (1997). “DMT is Everywhere”. TiHKAL: The Continuation. United States: Transform Press. p. 277. ISBN 0-9630096-9-9. . Gallimore, Andrew R.; Strassman, Rick J. (2016). “A Model for the Application of Target-Controlled Intravenous Infusion for a Prolonged Immersive DMT Psychedelic Experience”. doi:10.3389/fphar.2016.00211 . Nichols, David E. (2016). Barker, Eric L., ed. “Psychedelics”. Pharmacological Reviews. 68 (2): 264–355. doi:10.1124/pr.115.011478 . Lüscher, Christian; Ungless, Mark A. (2006). “The Mechanistic Classification of Addictive Drugs”. PLOS Medicine. 3 (11). doi:10.1371/journal.pmed.0030437. . Strassmann, Rick (1984). “Adverse reactions to psychedelic drugs. A review of the literature”. Journal of Nervous and Mental Disease. 172 (10): 577–595. doi:10.1097/00005053-198410000-00001 . .Fontanilla, D.; Johannessen, M.; Hajipour, A. R.; Cozzi, N. V.; Jackson, M. B.; Ruoho, A. E. (2009). “The Hallucinogen N,N-Dimethyltryptamine (DMT) Is an Endogenous Sigma-1 Receptor Regulator”. Science. 323 (5916): 934–937. doi:10.1126/science.1166127. . Strassman, Rick J. (1995). “Human psychopharmacology of N,N-dimethyltryptamine”. Behavioural Brain Research. 73 (1-2): 121–124. doi:10.1016/0166-4328(96)00081-2. . Ott, Jonathan. Pharmacotheon: Entheogenic Drugs, Their Plant Sources and History Paperback – January 1, 1993. . Strassman, R. (2001). DMT: The spirit molecule: A doctor’s revolutionary research into the biology of near-death and mystical experiences. Park Street Press.