Amiodarone therapy effects on childhood thyroid function.

Thyroid function was systematically evaluated in 15 consecutive children (mean age 13.7 years, range 0.5 to 19.5 years) before and serially during treatment with amiodarone (Cordarone), a potent antiarrhythmic agent. Amiodarone is known to affect thyroid homeostasis by competitive inhibition of 5'-monodeiodinase, which converts L-thyroxine (T4) to triiodothyronine (T3) and reverse T3 (rT3) to 3,3'-diodothyronine (T2), and also by the direct …