PROPYLTHIOURACIL IN THYROTOXICOSIS

Propylthiouracil has been recommended by Astwood and VanderLaan1as an effective substitute for thiouracil. Its antithyroid action in rats is approximately ten times that of thiouracil, and while it is more toxic than the latter on a weight basis, it is less toxic in quantities having a comparable therapeutic effect. Clinical observations oh the first 52 patients treated1point out that with few exceptions, 50 to 75 mg. propylthiouracil a day is an adequate initial dose, while 25 to 50 mg. a day is sufficient for maintenance. The antithyroid action is less intense than that of thiouracil; myxedema and thyroid enlargement have occurred only infrequently, and side reactions, not at all. From this study it appears that the new drug has approximately five times the activity of thiouracil, with few if any of the obstacles presented by the latter. Fifty-four patients have been treated with propylthiouracil by me