What is melatonin?

Melatonin is a hormone that is naturally produced in the body which is used in the regulation of the sleep-wake cycle. Melatonin is a purchasable OTC outside the pharmacy that can be used whenever needed to help induce sleep. In the United States, melatonin has become a very common supplement found in many households. The use in both adults and children to help prevent sleep disturbances can be beneficial for the quality of sleep that can be attained. The only concern comes from the lack of guidelines and data available in order to properly treat sleep disturbances. Since melatonin is not supervised by the FDA as it is a supplement, the contents within them are not 100% accurate. The purity within melatonin supplements are not consistent in production which can lead to possible larger dosages than expected. It is also common that storage of melatonin supplements within households is not as secure compared to prescription medications due to lack of knowledge on toxicity with regards to melatonin. This has led to many accidental overdoses in children who get access to these supplements expecting it to be candy.

What happens in melatonin toxicity?

Melatonin toxicity occurs when doses larger than recommended are ingested. It is common to see adolescents and children toxicity cases due to the smaller amount of melatonin required in order to be harmful. Depending on age, gender, sleep issues and health conditions toxic doses recommended can vary from person to person. Studies have shown doses over 3mg for children and over 10mg for adults start to show signs and symptoms of harm. Common symptoms that would occur from excessive melatonin would be slowed breathing, nausea, vomiting, confusion or disorientation, dizziness and excessive daytime sleepiness. 

What’s happening currently and why is it occurring?

Currently, studies from 2021 by the Poison Control center have found that there have been more than 52,000 calls about overconsumption of melatonin in children. Pediatric melatonin ingestion has accounted for 4.9% of the reported calls to the Poison Control center compared to the 0.6% of 2021. Over the past decade, there have been about 4,000 hospitalizations in which five children had to be hospitalized on a ventilation machine and two that had experienced death. This is a 6-fold increase since the past decade for this type of toxicity. The large increase in melatonin toxicity cases are commonly occurring from lack of storage precautions for the supplement. Children are able to access the melatonin bottles and assume it is candy in which they ingest more than the recommended amount which leads to toxicity. This has led to many hospitalizations over the past few years. Another concerning factor that has caused toxicity is overdosing in children by parents. As there is no regulation on how much melatonin can be given to anyone, parents have given more than the recommended amount which leads to toxicity as well. In certain cases, parents are giving their children more than the recommended dosage of melatonin due to their children building up a tolerance to the constant use of melatonin. This has led to the overuse of melatonin and toxicity from the over dosing of it. Overall, there should be better regulations for melatonin so that these cases of toxicity are less frequent in the future.


Nathan Nguyen

PharmD Candidate 2023

Temple University School of Pharmacy


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Esposito S, Laino D, D’Alonzo R, Mencarelli A, Di Genova L, Fattorusso A, Argentiero A, Mencaroni E. Pediatric sleep disturbances and treatment with melatonin. J Transl Med. 2019 Mar 12;17(1):77. doi: 10.1186/s12967-019-1835-1. PMID: 30871585; PMCID: PMC6419450.

Poison Control. https://www.poison.org/. Accessed June 9, 2022. 

Lelak K, Vohra V, Neuman MI, Toce MS, Sethuraman U. Pediatric Melatonin Ingestions — United States, 2012–2021. MMWR Morb Mortal Wkly Rep 2022;71:725–729. DOI: http://dx.doi.org/10.15585/mmwr.mm7122a1 Accessed June 9th, 2022