Melatonin
Melatonin is a hormone the brain makes in darkness. NCCIH says short-term supplement use appears safe for most people, that U.S. products are regulated as dietary supplements, and that a 2017 test of 31 products often found labeled amounts that did not match the bottle. Practice guidelines it cites do not recommend melatonin for chronic insomnia.
Melatonin is a hormone the brain produces in response to darkness. NCCIH says it helps with the timing of circadian rhythms and with sleep, and that light at night can block its production. Dietary melatonin supplements are usually made synthetically. NIH ODS has no dedicated melatonin fact sheet.
What is melatonin?
NCCIH describes melatonin as a hormone of darkness, not as a conventional sedative. The page also says melatonin may have other roles that are not fully understood. This entry stays with that description.
Does melatonin help with insomnia?
NCCIH reports that the American Academy of Sleep Medicine (2017) and the American College of Physicians (2016) found there is not enough strong evidence on effectiveness or safety to recommend melatonin for chronic insomnia. The ACP guideline it cites strongly recommends cognitive behavioral therapy for insomnia as an initial approach.
NCCIH separately summarizes research on jet lag, delayed sleep-wake phase disorder, some pediatric sleep problems, and anxiety around surgery. Those summaries are on the source page. This site is not building traffic pages around them.
How much melatonin is used?
NCCIH does not publish a single adult milligram figure as a standard dose. It notes that at amounts higher than the body normally produces, overall safety is still unclear. Short-term use appears safe for most people. Long-term safety data are lacking.
In several other countries, NCCIH says, melatonin is a prescription drug. In the United States it is a dietary supplement and is regulated less strictly than a drug.
How accurate are melatonin labels?
NCCIH cites a 2017 study of 31 melatonin supplements from grocery stores and pharmacies. For most products, the amount of melatonin did not match the label. Twenty-six percent contained serotonin.
That is a product-quality finding, not a dose recommendation.
Is melatonin safe for children?
NCCIH says parents should speak with a health care provider first. It lists uncertainties about dose, timing, long-term use, and whether benefits outweigh possible risks, including possible effects on hormonal development.
NCCIH also flags people with epilepsy and people on blood thinners as groups that need medical supervision if melatonin is considered, and it reports that the 2015 AASM guidelines recommend against melatonin in people with dementia.
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Sources
- Melatonin: What You Need To Know. National Center for Complementary and Integrative Health. https://www.nccih.nih.gov/health/melatonin-what-you-need-to-know Accessed 2026-08-18.