More Than Meets the Eye With Melatonin Labeling?

Volume 27, Issue 1

Melatonin is a hormone that helps regulate circadian rhythms and sleep. Exogenous replacement with melatonin supplements has been touted as a remedy for insomnia for decades. 

The amount of melatonin needed to induce sleep is very small and is often exceeded in the most common supplements. This is important as melatonin can produce side effects such as excessive daytime sleepiness, vivid dreams, and nightmares. Furthermore, since melatonin is considered a natural product, it is only regulated as a dietary supplement by the US Food and Drug Administration, so there is no guarantee that the label will reflect the actual content of the pills. 

In this week’s issue of Talking Therapeutics, we look at a new study that examined the contents of several commonly sold melatonin products. 

Point 1: More Than Meets the Eye

In this new paper, the authors sought to examine the melatonin content of common gummy products. The research was prompted by the fact that the number of calls for pediatric melatonin ingestions to US Poison Control Centers increased by 530% from 2012 to 2021, during which time there was also a significant number of emergency room visits and hospitalizations associated with melatonin poisoning. 

Of the 25 products they analyzed, 22 (88%) had inaccurate labels and only 3 (12%) contained melatonin at levels within 10% of the quantity indicated on the label.

In one product, researchers found no detectable levels of melatonin but 31.3 mg of cannabidiol (CBD), an active ingredient in cannabis. The amount of melatonin in the rest of the products they studied ranged from 1.3 mg to 13.1 mg per serving. Additionally, products with melatonin contained actual quantities ranging from 74% to 347% of the amount listed on the label.

Five products declared CBD. The quantity of CBD in each product ranged from 10.6 mg to 31.3 mg per serving, representing 104% to 118% of the quantities indicated on the label.

Point 2: Don’t Trust the Label

These findings are quite striking and indicate the labels for many commercially available melatonin products may not be accurate. The findings regarding the quantities of CBD are also startling, given that this compound has a greater propensity for neuropsychiatric side effects than melatonin. 

It is important to note these findings may not be generalizable to all melatonin products sold in the United States. However, given the findings of this study and the rising rate of emergency room visits and hospitalizations, pharmacists should counsel every patient purchasing melatonin products about the potential hazards involved.