The Centers for Disease Control and Prevention published a study last week that found melatonin poisoning in children had increased significantly during the pandemic.

Melatonin is a naturally occurring hormone that can help induce sleepiness. It is widely available over the counter.

Researchers led by Dr. Karima Lelak, an emergency physician at Children’s Hospital of Michigan, analyzed reports to poison control centers from 2012 to 2021 and found that annual melatonin overdoses by children increased by a factor of 530%, the overwhelming majority of which were unintentional ingestions.

The study also noted an increase in child hospitalizations due to melatonin poisoning, with the most significant increases occurring in 2020 and 2021.

Roughly 4,000 children suffered hospitalization over the 10-year period of study. Five ended up on ventilators, two of which died.

A melatonin overdose can result in nausea, migraines, diarrhea, restlessness, and joint pain. Cardiovascular and neurological systems can also be affected.

Children showed no symptoms in about 83% of the study’s reported cases. But in the others, reports indicated children experienced vomiting and altered breathing, among other symptoms.

On the possible causes of the increase in cases during 2020 and 2021, Lelak commented, “This might be related to increased accessibility of melatonin during the pandemic, as children spent more time at home because of stay-at-home orders and school closures. Further, reports of increasing sleep disturbances during the pandemic might have led to increased availability of melatonin in the home.”

Lelak noted that the data revealed significant variability in the active ingredient content of melatonin across retail brands, as high as 478% in some cases and as high as 465% between lots of the same product.

While many families find melatonin beneficial, the study cautions parents to consider that melatonin is regulated by the U.S. Food and Drug Administration as a “dietary supplement” as opposed to a drug.

Consequently, the FDA is under no obligation to investigate the purity of the elements used to manufacture the hormone, nor does it regulate the dosage.