title: Acute changes in thyroid function in patients treated with radioactive iodine.
abstract: Serum triiodothyronine (T3) and thyroxine (T4) were measured in thirteen unselected hyperthyroid patients before and at frequent intervals after iodine-131 treatment. There was an abrupt rise in  T3 from a pretreatment mean of 250 ng/100 ml to a maximum of 365 ng/100 ml at 24 hours. Total T4 rose from a mean of 18.7 mug/100 ml to a maximum of 22.3 mug/100 ml at 24-48 hours. These findings may explain why an occasional patient develops acute thyroid crisis after radioiodine treatment.
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D006980:Hyperthyroidism / Q000532:radiotherapy*; D007457:Iodine Radioisotopes / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D011879:Radiotherapy Dosage; D013958:Thyroid Crisis / Q000209:etiology; D013961:Thyroid Gland / Q000503:physiopathology*; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
chemical_list: D007457:Iodine Radioisotopes; D014284:Triiodothyronine; D013974:Thyroxine