Is it safe for a child to take melatonin (melatonin) every night?

Melatonin Use in Children: Safety and Recommendations

Daily melatonin use in children is not recommended for long-term use due to limited safety data, though short-term use may be appropriate for specific sleep disorders under healthcare supervision. 1, 2

Safety Profile and Concerns

• Melatonin has been studied primarily for specific sleep disorders in children, particularly Delayed Sleep-Wake Phase Disorder (DSWPD), with only moderate evidence supporting its short-term use 1
• No serious adverse reactions have been documented in relation to melatonin use in children, but rigorous long-term safety data are lacking 1
• Common mild-to-moderate side effects include daytime sleepiness (1.66%), headache (0.74%), dizziness (0.74%), and hypothermia (0.62%) 3
• Morning grogginess and "hangover" effects are more commonly reported with higher doses due to melatonin's half-life extending into morning hours 2

Appropriate Clinical Use

• Melatonin should only be used after behavioral interventions and sleep hygiene measures have failed 4
• For children with DSWPD without comorbidities, the American Academy of Sleep Medicine suggests a weight-based dose of 0.15 mg/kg taken 1.5-2 hours before habitual bedtime 1
• For children with DSWPD and psychiatric comorbidities (such as ADHD), fast-release melatonin at 3-5 mg may be effective 1
• In children with autism spectrum disorders, melatonin has shown effectiveness for improving sleep duration, latency, and reducing night wakings 1

Dosing Recommendations

• Lower doses of melatonin are often more effective than higher doses due to potential receptor desensitization at higher doses 2
• Weight-based approach is recommended: 0.15 mg/kg for children without comorbidities, or 3 mg if <40 kg and 5 mg if >40 kg for those with psychiatric comorbidities 1
• Timing is crucial: administration should be 1.5-2 hours before desired bedtime for optimal effect 1

Important Caveats

• Melatonin is regulated as a dietary supplement in the US, raising concerns about purity and reliability of stated doses 2
• Parents frequently initiate melatonin use without medical supervision (50% self-initiated, only 48.1% following healthcare provider recommendation) 5
• The American Academy of Sleep Medicine only provides a "weak for" recommendation regarding melatonin use in children, indicating uncertainty in the benefits/harms assessment 1
• Treatment duration in most studies was short (6 nights to 4 weeks), with very limited data on long-term safety beyond several months 1, 3

Recommended Approach

• Start with behavioral interventions and proper sleep hygiene before considering melatonin 4
• If melatonin is deemed necessary, use the lowest effective dose based on the child's condition 2
• Monitor for effectiveness and side effects, with regular reassessment of the need for continued use 4
• Consider discontinuation if the child no longer needs it or experiences negative side effects 5
• Obtain informed consent from both patient and caregiver regarding the limited long-term safety data 1

Given the lack of robust long-term safety data and the fact that many parents administer melatonin without medical guidance, nightly use of melatonin in children should be approached with caution and limited to specific clinical scenarios under healthcare supervision.