Maximum Dosage of Melatonin
The maximum recommended dose of melatonin for adults is 15 mg per day, though most therapeutic effects can be achieved at lower doses ranging from 1-5 mg. 1
Dosage Recommendations by Age Group and Condition
Adults
- For REM sleep behavior disorder (RBD): Start with 3 mg at bedtime, may titrate up in 3 mg increments to a maximum of 15 mg 1
- For insomnia: 1-5 mg is typically effective, with limited evidence supporting higher doses 1
- For delayed sleep-wake phase disorder (DSWPD): 5 mg taken between 19:00-21:00 has shown efficacy 1
Children and Adolescents
- For children with DSWPD without comorbidities: 0.15 mg/kg (approximately 1.6-4.4 mg based on weight) taken 1.5-2 hours before habitual bedtime 1
- For children/adolescents with DSWPD and psychiatric comorbidities (e.g., ADHD): 3-5 mg of fast-release melatonin 1
- General pediatric dosing: 0.5-3 mg for children and 3-5 mg for adolescents 2
Elderly
- For elderly with insomnia: 1-6 mg is typically effective 2, 3
- Lower doses may be preferable to start (0.5-2 mg) due to age-related changes in metabolism 4
Formulation Considerations
- Immediate-release melatonin is preferred for sleep onset difficulties 1
- Slow-release formulations appear less effective for some conditions like RBD 1
- Fast-release formulations have shown better efficacy in children with DSWPD and psychiatric comorbidities 1
Safety Profile and Adverse Effects
- Melatonin is generally well-tolerated with few adverse effects at recommended doses 5
- Most common adverse effects include:
- Most adverse effects resolve spontaneously within days or upon discontinuation 5
- No serious adverse effects have been reported in clinical trials at standard doses 5
Clinical Considerations and Caveats
- Bioavailability and content may vary across formulations, especially in countries where melatonin is sold as a dietary supplement rather than a prescription medication 1
- Look for products with the U.S. Pharmacopeia Verification Mark to ensure stated dose accuracy 1
- Regulatory status varies by country:
- Long-term safety data from randomized controlled trials is limited 5
- For jet lag prevention, doses between 0.5-5 mg are similarly effective, with 5 mg providing slightly better sleep quality than lower doses 6
Special Populations
- Caution is advised in patients with epilepsy or those taking warfarin, as case reports suggest potential interactions 6
- For children and adolescents, informed consent from caregivers is recommended due to limited long-term safety data 1
While melatonin has a wide therapeutic window, there is no evidence supporting doses above 15 mg for any condition, and most therapeutic effects can be achieved with much lower doses.