[The influence of etiroxat-HCl on iodine metabolism in man (author's transl)].

Investigation of the iodine metabolism in man during and after the ingestion of D,L-methyl-3,5,3,5-tetraiodothyronine-ethylester-hydrochloride (etiroxat-hydrochloride, Skleronorm) exhibited the following results: 1. After 20-40 mg of etiroxat the absolute iodine uptake of the thyroid gland was increased 3-7 times. There was indirect evidence that the incretion rate of thyroid hormones did not change. 2. The concentration of total iodine, T4(D), T4(RIA) and T3(RIA) was artificially increased by etiroxat for 2-3 months after cessation of its application. Therefore these parameters do not offer information on the concentration of thyroid hormones in the blood during this period of time. 3. Like other thyroid hormone analogues 40 mg etiroxat daily for 4 weeks blocks the TSH incretion induced by 200 microng TRH up to 1-2 weeks after cessation.