The superiority of synthetic levothyroxine sodium over thyroid extracts in the treatment of hypothyroidism seems established. The exciting developments in our understanding of thyroid physiology during recent years must parallel the excitement that accompanied the first demonstration of the effective control of hypothyroidism by the use of extracts from animal thyroid glands. Those of us who have witnessed some of these advances remember the excitement that they produced, and we have enjoyed and appreciated the advantages that they have provided. Progress is always rewarding, and I agree with Penny and Frasier (p 16) that synthetic levothyroxine is the drug of choice in the treatment of hypothyroidism in the year 1979. However, I am compelled to add a word in defense of an old and reliable friend, namely, the little gray pill of USP desiccated thyroid. To do less would seem unjust.
For many years, I have prescribed levothyroxine for my