Vit. B 12 in Thyrotoxicosis and Myxedema. ∗

Abstract

Summary

The whole-blood B₁₂ values in 10 hyperthyroid subjects before and after a load dose of B₁₂ were lower than for a normal and a myxedematous group. The mean 8-hour urinary excretion after B₁₂ administration in hyperthyroid subjects was considerably lower than in the normal and myxedematous groups. These data suggest that B₁₂ turnover and demand is appreciably greater in hyperthyroidism and appreciably lower in myxedema.