التداخل بين إستراديول ودينوجيست وليفوثيروكسين وليوثيرونين

Estrogen, Oral Contraceptives — Estrogens tend to increase serum thyroxine-binding globulin (TBg).

In a patient with a nonfunctioning thyroid gland who is receiving thyroid replacement therapy, free levothyroxine may be decreased when estrogens are started thus increasing thyroid requirements.

Therefore, patients without a functioning thyroid gland who are on thyroid replacement therapy may need to increase their thyroid dose if estrogens or estrogen-containing oral contraceptives are given.

Women on thyroid hormone replacement therapy may need increased doses of thyroid hormone because serum concentrations of thyroid-binding globulin increase with use of COCs [see Clinical Pharmacology ( 12.3 )] .

Consult the labeling of the concurrently-used drug to obtain further information about interactions with COCs or the potential for enzyme alterations. [See Clinical Pharmacology ( 12.3 ).] Women on thyroid hormone replacement therapy may need increased doses of thyroid hormone because serum concentrations of thyroid-binding globulin increase with use of COCs.