The Therapeutic Potential of Melatonin: A Review of the Science

Samir Malhotra, MD; Girish Sawhney, MD; Promila Pandhi, MD

In This Article


Melatonin has the potential to be of use in a large number of disorders of different etiologies. However, unequivocal evidence of its efficacy has been established only for a few conditions -- jet lag, depression, and insomnia. It has not yet been possible to effectively determine the immunomodulatory effects of melatonin because both immunosuppression and immunoenhancement have been observed in different settings. The oncostatic use of melatonin may become a part of an anticancer drug regimen. An anticonvulsant effect of melatonin has been consistently observed in animal models, but proof from well-controlled clinical trials is still lacking.

Some evidence suggests an antioxidant role of melatonin with the possibilities of beneficial effects in Alzheimer's disease; parkinsonism; and cardiovascular, gastrointestinal, and renal disorders. Definite evidence for the role of melatonin as an antiaging compound has not been obtained.

Melatonin can cause adverse effects, and long-term safety data are lacking. Furthermore, no information is available concerning the possibility of interactions with either prescription or nonprescription medications. Available in many countries as a nutritional adjunct, melatonin has managed to evade the drug-regulatory authorities. This has led to unregulated and uncontrolled use of melatonin, which must be prevented unless and until clear benefits are demonstrated.


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