Dimethyltryptamine (DMT) has a long history of use worldwide as it is found in a variety of plants and seeds, and can also be produced synthetically. It is ineffective when taken orally unless combined with another drug that inhibits its metabolism. Generally it is sniffed, smoked or injected. The effective hallucinogenic dose in humans is about 50 to 100 milligrams and lasts for about 45 to 60 minutes. Because the effects last only about an hour, the experience was called a "businessman's trip."

A number of other hallucinogens have very similar structures and properties to those of DMT, Diethyltryptamine (DET), for example, is an analogue of DMT and produces the same pharmacological effects but is somewhat less potent than DMT. Alpha-ethyltryptamine (AET) is another tryptamine hallucinogen recently added to the list of Schedule I substances in the CSA.