Complete dosing information for levothyroxine sodium
Medical guidance required: Dosing information here is for educational purposes. Your healthcare provider will determine the appropriate dose based on your specific condition, kidney function, other medications, and medical history. Never adjust your dose without consulting your doctor or pharmacist.
Hypothyroidism (typical): 1.6 mcg/kg/day; start 25–50 mcg/day in elderly or cardiac patients; adjust q6–8 weeks based on TSH; TSH suppression (thyroid cancer): 2.0–2.2 mcg/kg/day to achieve suppressed TSH <0.1 mIU/L; Myxedema coma (IV): 200–400 mcg IV loading dose; then 100–200 mcg/day
Congenital hypothyroidism: 10–15 mcg/kg/day (neonates). Dose decreases per kg as child grows.
No dose adjustment required; monitor TSH.
Use with caution in severe liver disease due to altered protein binding.