Abstract
This study fails to confirm the entity of metabolic insufficiency, in which parients are said to show symptoms suggesting hypothyroidism, a low basal metabloic rate, normal thyroid function by other tests, and a response to triiodothyronine but not to desiccated thyroid. In a double-blind study of 20 cases, as many patients improved during treatment with placebo as with triiodothyronine. In 12 patients with normal levels of serum protein-bound iodine, the control of fatique and elevation of BMR were as satisfactory with desiccated thyroid as with triiodothyronine when equivalent doses were used. Triiodothyronine was used in therapeutic trials in 132 cases of suspected hypothyroidism''. It has advantages for such use because of the rapidity of onset and cessation of its action. Thus an acceptable BMR level is reached with two weeks and symptoms of overdosage are readily recognized. The dose varied from 25 to 150 [mu]g. An overdose resulted more often in nervousness than in cardiac consciousness. Desiccated thyroid was preferred for long-term use.