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Minimal Invasive Resection of Large Retrosternal Thyroid Goiter
Published on: September 20, 2024
Goserelin-induced transient thyrotoxicosis in a hypothyroid woman on L-thyroxine replacement
1Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, The Netherlands. a.c.vanbon@amc.nl
An increase in free thyroxine (fT4) and a decrease in thyroid-stimulating hormone (TSH) was observed in a hypothyroid woman on levothyroxine treatment after implantation of goserelin, a gonadotropin-releasing hormone (GnRH) analogue. In the literature no data are available that describe a drug interaction between GnRH analogues and thyroid hormone replacement. Our hypothesis to explain this observation is that goserelin decreased serum thyroxine-binding-globulin (TBG), resulting in an increase in fT4 and thereby a decrease in serum TSH.
An increase in free thyroxine (fT4) and a decrease in thyroid-stimulating hormone (TSH) was observed in a hypothyroid woman on levothyroxine treatment after implantation of goserelin, a gonadotropin-releasing hormone (GnRH) analogue. In the literature no data are available that describe a drug interaction between GnRH analogues and thyroid hormone replacement. Our hypothesis to explain this observation is that goserelin decreased serum thyroxine-binding-globulin (TBG), resulting in an increase in fT4 and thereby a decrease in serum TSH.
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