Dimethyltryptamine (DMT) belongs to a class of chemical compounds called ‘tryptamines’ which mainly modulate amounts of serotonin (a neurotransmitter involved in the regulation of mood, appetite, sleep and memory) throughout the central nervous system.

DMT has been found naturally in humans although it has yet to be confirmed whether it is actually made in the body.

The hallucinogenic effects of DMT reach their peak quickly when it is taken intravenously (around 2 minutes), take slightly longer to be reached following injection into muscle (between 10-15 minutes) and are slowest when the commonly-used oral route is used (1-2 hours).  The time taken to reach peak effects following smoking of DMT is yet to be accurately measured.

A digestive enzyme present in the body called monoamine oxidase, breaks down DMT when it is taken orally.  For this reason, when taken orally, DMT must be combined with an inhibitor of this enzyme –a monoamine oxidase inhibitor (MAOI) such as the ayahuasca vine, found and widely used in South America.  MAOIs both prolong the duration and increase the intensity of DMTs pharmacological effects.  They also interact with a host of other drugs and should be used with caution.

Once taken, DMT binds to several types of serotonin receptor and at a few of these; its stimulating action has been confirmed.  DMT has a notably high affinity for one such receptor –the serotonin 2C receptor (or 5-HT2C receptor).  Stimulation of this receptor is known to induce the hallucinogenic effects seen with DMT while serotonin produced inhibits both dopamine (a neurotransmitter involved in reward-seeking behaviour) and adrenaline (a neurotransmitter and hormone involved in stress regulation). 

In addition to the intense but relatively short hallucinations, users may also experience effects including: dilated pupils; increased heart rate; increased blood pressure and euphoria.

At particularly high doses, feelings of incapacitation can overwhelm the hallucinogenic effects of DMT.