Levothyroxine Pediatric Dosing
Thyroid hormone replacement dosing for congenital and acquired hypothyroidism in children.
Weight in kilograms
Age in months
Reason for replacement
⚠️ Warnings & Contraindications
- CRITICAL for neurodevelopment: start treatment ASAP in congenital hypothyroidism (within 2 weeks of life)
- Overdose causes signs of hyperthyroidism: tachycardia, tremor, hyperactivity, poor weight gain
- Underdose causes developmental delay and poor growth
- Give on empty stomach, 30-60 minutes before breakfast
- Absorption affected by soy formula, calcium, iron, and antacids - separate by 4 hours
- Crushable tablets are available; liquid suspension is not stable
ℹ️ Clinical Notes
Tablets: 25 mcg, 50 mcg, 75 mcg, 88 mcg, 100 mcg, 112 mcg, 125 mcg, 137 mcg, 150 mcg, 175 mcg, 200 mcg, 300 mcg. Can crush tablets and mix with small amount of water/formula.
References
- AAP Guidelines for congenital hypothyroidism - AAP/Pediatrics (2006)
- Levothyroxine pediatric dosing - Drugs.com (2026)
Medical Disclaimer
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