title: Iatrogenic hyperthyroidism secondary to dextrothyroxine administration.
abstract: Two patients are reported who presented with clinical hyperthyroidism, increased serum thyroid function studies, and depressed radioactive iodine uptake, secondary to chronic ingestion of D-T4. Symptoms abated, and function studies returned to normal, following discontinuation of D-T4. This uncommon effect of D-T4 may be more prevalent than is generally realized and must be recognized as another potential cause of low radioiodine uptake in patients with clinical hyperthyroidism.
mesh_terms: D000368:Aged; D003918:Dextrothyroxine / Q000009:adverse effects*; D005260:Female; D006801:Humans; D006937:Hypercholesterolemia / Q000188:drug therapy; D006980:Hyperthyroidism / Q000139:chemically induced* / Q000532:radiotherapy; D007457:Iodine Radioisotopes / Q000378:metabolism / Q000627:therapeutic use; D008875:Middle Aged; D013960:Thyroid Function Tests
chemical_list: D007457:Iodine Radioisotopes; D003918:Dextrothyroxine