Melatonin, or 5-methoxy-N-acetyltryptamine, is a hormone produced by pinealocytes in the pineal gland, located in the brain, but also in the retina and GI tract. It is a derivative of the amino acid tryptophan.

GoldBamboo

... In the United States, supplemental melatonin is mostly for the short-term relief of sleep disturbances -- especially jet lag. Results from several controlled studies show that melatonin taken before, during, and after long-distance travel may lessen or prevent sleep disruption. In addition, melatonin may be associated with less daytime drowsiness than prescription sleeping pills. Although it is not approved as a regular prescription drug, melatonin does have a special orphan drug designation from the U.S. Food and Drug Administration (FDA). An orphan drug has extremely limited uses, such as for the treatment of a rare disease. Melatonin is prescribed as an orphan drug for blind individuals who suffer from sleep disturbances because their daily rhythm is distorted by the lack of light-and-dark effects that help to regulate sleeping cycles in sighted individuals. Melatonin is also available as a dietary supplement without a prescription. ...
Drug Digest - more...

Melatonin Systematic (IUPAC) name N-[2-(5-methoxy-1H-indol-3-y ...
Wikipedia - [full article]

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