Resistance of Normal Human Thyroids to Propylthiouracil. ∗ †

Abstract

Summary

Propylthiouracil was administered to 8 euthyroid women over a period of 7½ months in large dosage. No evidence of hypothyroidism was noted, i.e., no change of basal metabolic rate, no alteration of menstrual cycles, no clinical signs or symptoms of hypothyroidism, and no thyroid enlargement. No toxic manifestations were noted, even though during the final 6 weeks, each patient received 3000 mg of propylthiouracil daily in divided doses.