Amiodarone-induced neonatal hypothyroidism: a unique form of transient early-onset hypothyroidism.

Amiodarone is an iodine-rich drug used to treat cardiac dysrhythmias. The structure of amiodarone resembles that of thyroxine, and treatment with amiodarone may alter thyroid function. The effects of antenatal amiodarone use on fetal/neonatal thyroid function have only been addressed in a limited number of patient reports. We describe two cases of transient neonatal hypothyroidism due to in utero amiodarone exposure, followed by a brief review of the available literature.