The Biologic Effects of D-Thyroxine

Abstract
Comparison of D- and L-thyroxine for calorigenicity, antigoitrogenicity, effect on metamorphosis of the tadpole, effects on cholesterol metabolism, cardiac effects, tissue localization, and toxicity reveals a quantitative and useful separation of biological effects. Tests in the mouse, rat, rabbit, and dog provide a basis for the selection of a dose of D-thyroxine which will decrease serum and liver cholesterol concentrations markedly in man without noticeable calorigenic, cardiac, or toxic effects.