Goserelin-induced transient thyrotoxicosis in a hypothyroid woman on L-thyroxine replacement.
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.
van Bon
A C
AC
Department of Endocrinology and Metabolism, Academic Medical Center, University of Amsterdam, The Netherlands. a.c.vanbon@amc.nl
Wiersinga
W M
WM
D000328:Adult; D018931:Antineoplastic Agents, Hormonal / Q000008:administration & dosage / Q000009:adverse effects*; D004343:Drug Implants / Q000009:adverse effects; D004347:Drug Interactions; D005260:Female; D017273:Goserelin / Q000008:administration & dosage / Q000009:adverse effects*; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000188:drug therapy*; D013971:Thyrotoxicosis / Q000097:blood / Q000139:chemically induced*; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood / Q000627:therapeutic use*
D018931:Antineoplastic Agents, Hormonal; D004343:Drug Implants; D017273:Goserelin; D013972:Thyrotropin; D013974:Thyroxine