The TSH Test as an Aid in Diagnosing Hypothyroidism

Abstract

A thyrotropin test using a single dose of 5 units with a three hour iodine 131 uptake and serum protein-bound iodine measurement before and 24 hours after the injection compares favorably with tests using other schedules. This test is most often of clinical value in detecting borderline cases of hypothyroidism in which other tests of thyroid function are equivocal and in subjects who have been taking thyroid medication without clear evidence of hypothyroidism.