The side effects of DMT include agitation, increase in the heart rate and hallucinations, according to the National Institute on Drug Abuse. The hallucinations are often very bizarre, sometimes horrifying, and include the belief that the user's body or environment have undergone distortions.
The hallucinations also include intense colors and kaleidoscopic patterns, says Psychology Today. About 60 percent of users report visitations from aliens or animals with human intelligence. These visitations are so compelling that the users believe they are real.
If there are any long-term effects of DMT, they are unknown, says the National Institute on Drug Abuse. Users do not build up a tolerance for the drug.
DMT, or dimethyltryptamine, acts on the 5-HT serotonin receptors in the central nervous system, according to the National Institute on Drug Abuse. Some researchers believe that humans have small amounts of this drug in the body naturally, and this may be responsible for reports of visitations by aliens and mystical or near-death experiences.
The drug is also present in some plants, such as the ones that go into the ayahuasca ritual, and can be man-made, claims the National Institute on Drug Abuse. As a synthetic, DMT is usually a white powder that people smoke in a pipe. Though intense, the effects last for about a half an hour, according to Psychology Today.