Effects of recombinant growth hormone therapy on thyroid hormone concentrations

Abstract

A transient decrease in T4 concentrations in the 3rd month with unchanged T3 and an increase in fT3 concentrations probably result from the effect of rGH on the peripheral metabolism of thyroid hormones. The results obtained do not support the use of thyroid hormone therapy with levothyroxine during the first year of rGH therapy in patients who are initially euthyroid.