5-Methoxytryptamine

5-Methoxytryptamine (5-MT, 5-MeO-T, or 5-OMe-T), also known as serotonin methyl ether or O-methylserotonin and as mexamine, is a tryptaminederivative closely related to the neurotransmittersserotonin and melatonin. It has been shown to occur naturally in the pineal gland of the brain. It is formed via O-methylation of serotonin or N-deacetylation of melatonin.

5-MT is a highly potent and non-selectiveserotonin receptor agonist and shows psychedelic-like effects in animals. However, it is inactive in humans, at least orally, likely due to rapid metabolism by monoamine oxidase (MAO). The levels and effects of 5-MT are dramatically potentiated by monoamine oxidase inhibitors (MAOIs) in animals.

5-MT was first described in the scientific literature by at least 1925.