The agency said that melatonin, which can come in gummies that are meant for adults, was implicated in about 7 percent of all emergency room visits for young children and infants "for unsupervised medication ingestions," adding that many incidents were linked to the ingestion of gummy formulations that were flavored. Those incidents occurred between the years 2019 and 2022.

Melatonin is a hormone produced by the human body to regulate its sleep cycle. Supplements, which are sold in a number of different formulas, are generally taken before falling asleep and are popular among people suffering from insomnia, jet lag, chronic pain, or other problems.

The supplement isn't regulated by the U.S. Food and Drug Administration and does not require child-resistant packaging. However, a number of supplement companies include caps or lids that are difficult for children to open.

The CDC report said that a significant number of melatonin-ingestion cases among young children were due to the children opening bottles that had not been properly closed or were within their reach. Thursday's report, the agency said, "highlights the importance of educating parents and other caregivers about keeping all medications and supplements (including gummies) out of children's reach and sight," including melatonin.

The approximately 11,000 emergency department visits for unsupervised melatonin ingestions by infants and young children during 2019–2022 highlight the importance of educating parents and other caregivers about keeping all medications and supplements (including gummies) out of children's reach and sight.

The CDC notes that melatonin use among Americans has increased five-fold over the past 25 years or so. That has coincided with a 530 percent increase in poison center calls for melatonin exposures to children between 2012 and 2021, it said, as well as a 420 percent increase in emergency visits for unsupervised melatonin ingestion by young children or infants between 2009 and 2020.