What is the recommended dosage of melatonin (melatonin) for adults and children?

Melatonin Dosing Recommendations

Direct Answer by Clinical Indication

For adults with Delayed Sleep-Wake Phase Disorder (DSWPD), use 5 mg of melatonin taken between 19:00-21:00 (7-9 PM) for at least 28 days; for children with DSWPD without comorbidities, use 0.15 mg/kg taken 1.5-2.0 hours before habitual bedtime; and melatonin should NOT be used for chronic insomnia in adults as it provides no clinically significant benefit. 1, 2, 3

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Adult Dosing Algorithm

Step 1: Identify the Sleep Disorder

For DSWPD (Delayed Sleep-Wake Phase Disorder):

• Administer 5 mg of melatonin between 19:00-21:00 (7-9 PM) for a minimum of 28 days 1, 2, 3
• This timing is critical: the dose must be given 1.5-2 hours before desired sleep onset, not at actual bedtime 2, 3
• This recommendation applies equally to adults with or without comorbid depression 1, 2
• Expected benefits include reduction in sleep latency by 37-44 minutes and increase in total sleep time by 41-56 minutes 1, 3

For Chronic Insomnia:

• Do NOT use melatonin - the American Academy of Sleep Medicine explicitly advises against melatonin for chronic insomnia based on trials showing no clinically significant benefit at 2 mg doses 2, 3
• The benefits were judged approximately equal to harms, with no improvements in sleep latency, total sleep time, wake after sleep onset, or sleep quality 2
• Consider FDA-approved hypnotics or cognitive behavioral therapy for insomnia (CBT-I) instead 2

Step 2: Dosing Considerations

Standard dosing range:

• Start with 3-5 mg for most sleep disorders 3
• Doses between 0.5-5 mg are similarly effective for DSWPD, except that 5 mg produces faster sleep onset and better sleep quality than 0.5 mg 1
• Doses above 5 mg appear no more effective and may cause receptor desensitization 3
• Maximum recommended dose is typically 12-15 mg, though doses above 10 mg risk receptor desensitization 3

Formulation matters:

• Use immediate-release melatonin, not slow-release formulations 1, 3
• The 2 mg slow-release formulation is relatively ineffective, suggesting that a short-lived higher peak concentration works better 1

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Pediatric Dosing Algorithm

For Children with DSWPD WITHOUT Comorbidities:

Use weight-based dosing at 0.15 mg/kg taken 1.5-2.0 hours before habitual bedtime 1, 3

• This translates to approximately 4.4 mg for an average child in the studied population 1
• Treatment duration as short as 6 nights has demonstrated effectiveness 1, 3
• This represents moderate-quality evidence from randomized controlled trials 1

For Children with DSWPD WITH Psychiatric Comorbidities:

Use fast-release melatonin with weight-based approach: 3

• 3 mg if child weighs <40 kg
• 5 mg if child weighs >40 kg
• Administer at 18:00-19:00 for 4 weeks 3

General Pediatric Dosing Ranges:

• Children: 0.5-3 mg 4
• Adolescents: 3-5 mg 4

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Critical Timing Considerations

The timing of melatonin administration is as important as the dose itself:

• For DSWPD: administer between 19:00-21:00 or 1.5-2 hours before desired sleep time 1, 2, 3
• If taken at the wrong time (early in the day), melatonin causes sleepiness and delays adaptation to local time 5
• Maintain consistent nightly timing throughout the treatment period 1

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Common Pitfalls and Caveats

Avoid these mistakes:

• Do not use melatonin for chronic insomnia - it is ineffective and represents inappropriate prescribing 2, 3
• Do not use slow-release formulations for sleep onset problems - they are less effective than immediate-release 1, 3
• Do not administer at bedtime - timing must be 1.5-2 hours before desired sleep 2, 3
• Do not exceed 5 mg for DSWPD unless treating other conditions, as higher doses offer no additional benefit and increase side effects 1, 3

Safety concerns:

• Exercise caution in patients taking warfarin due to potential interactions 3, 5
• Use caution in patients with epilepsy based on case reports of potential harm 3, 5
• Common mild side effects include morning headache, morning sleepiness, drowsiness, dizziness, and gastrointestinal upset 3, 6
• No serious adverse reactions have been documented across age groups when used at recommended doses 1, 3

Quality control:

• Choose United States Pharmacopeial Convention Verified formulations for most reliable dosing 3
• Many over-the-counter melatonin products have variable quality and actual melatonin content 3

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Evidence Quality and Strength

The recommendation for DSWPD is based on low-to-moderate quality evidence but represents the strongest available data 1, 2, 3. The American Academy of Sleep Medicine provides a weak recommendation FOR melatonin in DSWPD but a weak recommendation AGAINST melatonin in chronic insomnia 1, 2, 3. This divergence reflects the condition-specific efficacy: melatonin works by resetting circadian rhythms in DSWPD but does not address the underlying pathophysiology of chronic insomnia 2.