Melatonin, a naturally occurring hormone that regulates the sleep–wake cycle, has become a prominent topic in public health discussions amid the growing popularity of products marketed to improve sleep. Concerns have intensified following reports of widespread paediatric use in the United States, prompting renewed debate in Chile about the safety, regulation and appropriate use of melatonin-based products.

Although melatonin is produced by the human body, its classification varies internationally. In some countries it is sold as a dietary supplement, while in others it is regulated as a medicinal product. This distinction has contributed to markedly different usage patterns and levels of risk.

Rising concerns linked to paediatric exposure in the United States

In the United States, where melatonin is widely available as an over-the-counter supplement, consumption has increased sharply over the past decade. According to data reported by health authorities, more than 260,000 paediatric exposure cases were recorded between 2012 and 2021, representing an increase of nearly 500%.

Francisco Álvarez, an academic in Chemistry and Pharmacy at Universidad Andrés Bello in Chile, notes that emergency department visits, hospital admissions and severe neurological complications have been documented. These include seizures and altered levels of consciousness. One of the most significant risk factors identified is the presentation of melatonin in flavoured gummy formats, often containing high doses and visually appealing to young children, leading to accidental ingestion, particularly among those under five years of age.

The regulatory landscape in Chile

Chile maintains a more restrictive regulatory framework. Melatonin is primarily registered as a medicinal product and generally requires a prescription. However, experts caution that regulation alone does not eliminate risk. Between 2019 and 2022, nearly 1,000 consultations and reports related to melatonin overdose or interactions with other central nervous system depressants were received by the Chilean Poison Control Centre (CITUC) and the Institute of Public Health (ISP).

According to Álvarez, these figures demonstrate that unsupervised use remains a significant concern even in more tightly controlled settings. He stresses that melatonin use in children should always be individualised, limited in duration and conducted under strict medical supervision.

Potential health risks and symptoms

Excessive or inappropriate use of melatonin may lead to a range of adverse effects. Early symptoms of overdose can include excessive drowsiness, dizziness, confusion, rapid heart rate, low blood pressure and intense headaches. In more severe cases, persistent vomiting, convulsions, respiratory impairment and serious neurological disturbances have been reported, all of which require urgent medical attention.

Scientific literature has also highlighted uncertainties regarding long-term use, particularly in children, where the hormone may interfere with normal neurological and hormonal development.

Prevention through education and responsible use

Health experts in Chile emphasise that prevention must be strengthened through public education and responsible prescribing practices. In an era marked by widespread self-medication and the rapid spread of unverified health information online, clear guidance is essential.

Specialists agree that melatonin should not be regarded as a harmless or freely consumable product. Its use in children should be exceptional, time-limited and prescribed by a qualified professional. For adults, the same principle applies: medical guidance is recommended, and self-medication should be avoided.

As Álvarez concludes, reinforcing health education and regulatory awareness is critical to ensuring that a widely promoted sleep aid does not become a source of preventable harm.