TOLERANCE TO ORAL THYROID AND REACTION TO INTRAVENOUS THYROXINE IN SUBJECTS WITHOUT MYXEDEMA

Abstract

Certain non-myxedematous subjects tolerated as much as 6 grains of dried thyroid daily for long periods, without effect on the BMR or on pulse rate. Many others tolerated as much as 3 or 4 grains daily without effect on the BMR. These subjects responded to thyroxine intraven., but required much larger doses than did myxedematous subjects to produce a comparable rise in the BMR. This behavior was very different from the absence of tolerance and the acute sensitivity to thyroid and to thyroxine of the patient with myxedema. It is suggested as a working hypothesis that this difference of behavior can best be explained by assuming that the non-myxedematous subject possesses the ability, wanting in the patient with myxedema, to inactivate thyroid substance and intravenous thyroxine.