The RCH Pharmacy reminds prescribers of the risks associated with melatonin use in paediatric patients.
Melatonin is a pineal hormone that regulates the sleep-wake cycle. Although it is being increasingly prescribed to assist children with sleep, melatonin is not registered for use in children anywhere in the world and little is known about its long term effects on the human body.
In animals, however, there are significant known physiological effects on the reproductive, cardiovascular, metabolic and immune systems.
In primate studies, administration of melatonin 0.7 micrograms/kg/day advanced the onset of puberty by five months. Children taking melatonin are exposed to significantly higher mg/kg doses than those used in the primate studies (for example, a 15 kg child taking melatonin 3 mg receives 200 micrograms/kg/day).
The doses of melatonin used in paediatric patients (0.5 mg to 12 mg daily) are also significantly higher than the total daily production of melatonin in adults (20 to 60 micrograms over 8 to 10 hours per day).
The Therapeutic Goods Administration (TGA) advises that melatonin “…is not recommended for use in children and adolescents below 18 years of age due to insufficient data on safety and efficacy.”
In other parts of the world, the advice is stricter. The U.S. National Institute of Health (NIH) advises that melatonin “…should not be used in most children. It is possibly unsafe. Because of its effects on other hormones, melatonin might interfere with development during adolescence.”
At the RCH melatonin is a Drug Usage Committee (DUC) restricted medication and any prescribing indications outside the exempt criteria and all prescriptions commencing a patient on melatonin require DUC approval.
The ongoing need for melatonin should be reviewed at least every 3 months with consideration of the known physiological effects on other body systems in animals.
More information about the risks associated with melatonin in paediatric patients is available from the following review article:
Kennaway, D. J. (2015), Potential safety issues in the use of the hormone melatonin in paediatrics. J Paediatr Child Health, 51: 584–589
This article was written by Emily Porrello