Magnesium Dosing for Sleep in an 11-Year-Old Child
For an 11-year-old child with sleep problems, I recommend starting with 5-6 mg/kg/day of elemental magnesium (approximately 110-165 mg daily for an average-weight child), given 1-2 hours before bedtime, with careful monitoring for gastrointestinal side effects. 1
Dosing Framework
The American Academy of Pediatrics establishes a standard supplementation dose of approximately 5-6 mg/kg/day of elemental magnesium for children 1. For an 11-year-old child of average weight (approximately 35-40 kg), this translates to:
- Starting dose: 110-165 mg elemental magnesium daily
- Maximum safe dose: Should not exceed approximately 110-130 mg to minimize gastrointestinal effects in younger children, though an 11-year-old may tolerate slightly higher doses 1
- Timing: Administer 1-2 hours before habitual bedtime 2
Important Distinction: Melatonin vs. Magnesium
The strongest pediatric sleep evidence actually supports melatonin rather than magnesium for sleep disorders in children. Multiple high-quality studies demonstrate melatonin's efficacy:
- Optimal melatonin dosing for children: 0.15 mg/kg (approximately 4-6 mg for an 11-year-old), taken 1.5-2.0 hours before bedtime 2
- Melatonin doses of 3-6 mg have shown significant improvements in sleep latency (42 minutes improvement), sleep duration, and sleep anxiety in children aged 6-12 years 2
- Evidence quality for melatonin in pediatric sleep is MODERATE to LOW but consistently positive 2
In contrast, magnesium's sleep benefits in children lack direct high-quality evidence. Adult studies show benefits with magnesium combined with melatonin and zinc 3, but isolated magnesium for pediatric sleep has minimal supporting data.
Magnesium Formulation Considerations
If proceeding with magnesium supplementation:
- Magnesium bisglycinate is preferred for better gastrointestinal tolerance 1, 4
- Magnesium citrate (FDA-approved for children 6-12 years): 3-7 fl oz maximum per 24 hours, though this is labeled for laxative use, not sleep 5
- Avoid magnesium chloride in high doses due to increased anion gap and metabolic acidosis risk 2
Critical Safety Monitoring
Before initiating magnesium supplementation:
- Assess renal function: Magnesium is primarily renally excreted; contraindicated in severe renal impairment 1, 4
- Monitor for gastrointestinal effects: Diarrhea and abdominal cramping are the primary dose-limiting factors 1, 4
- Watch for hypermagnesemia signs: Muscle weakness, hypotension, bradycardia (rare with oral supplementation in children with normal renal function) 4
Absolute Contraindications
Do not use magnesium supplementation in children with:
- Severe renal impairment 1, 4
- Complete heart block or severe cardiac conduction abnormalities 1, 4
- Active gastrointestinal obstruction 1, 4
Clinical Recommendation Algorithm
Step 1: Consider melatonin as first-line therapy (stronger evidence base for pediatric sleep) 2
Step 2: If choosing magnesium instead or as adjunct:
- Start with 5 mg/kg/day elemental magnesium (approximately 130-150 mg for typical 11-year-old) 1
- Use magnesium bisglycinate formulation 1
- Administer 1-2 hours before bedtime 2
Step 3: Monitor response after 2-4 weeks:
- If no gastrointestinal side effects and inadequate response, may cautiously increase toward upper range
- If diarrhea develops, reduce dose by 25-50% 1, 4
Step 4: Do not exceed maximum recommended daily dose within 24 hours to avoid significant diarrhea and electrolyte disturbances 4
Common Pitfalls to Avoid
- Overlooking melatonin: The evidence for melatonin in pediatric sleep disorders is substantially stronger than for magnesium alone 2
- Excessive dosing: Higher magnesium doses primarily cause diarrhea without additional sleep benefits 1
- Ignoring renal function: Always assess kidney function before initiating supplementation 1, 4
- Wrong formulation: Magnesium oxide has poor absorption; magnesium citrate causes more GI effects than bisglycinate 1