More than one way to skin a thyroid. Managing pediatric hypothyroidism with weekly intramuscular levothyroxine

Oral levothyroxine (L-T4) supplementation is usually an effective therapy in pediatric hypothyroidism, except in patients with malabsorption or pseudomalabsorption. In these cases, parenteral L-T4 may be required, but there is a paucity of information about this delivery method in the pediatric population.

We present three cases of pediatric patients with primary hypothryoidism unresponsive to oral L-T4 that were successfully treated with intramuscular (IM) L-T4.

This is the first pediatric case series of successful IM L-T4 therapy in refractory primary hypothyroidism. Our case series demonstrates that once weekly IM L-T4 dosing may be a safe and well tolerated treatment regimen for pediatric patients.