Oral administration of orinase (tolbutamide); clinical observations of effect on nondiabetic and diabetic humans.

Ingestion of tolbutamide (Orinase(R)) by nondiabetic humans brought about a maximum reduction in blood sugar within one to two hours. In diabetic persons taking large doses of insulin, or who needed insulin for control, hyperglycemia, ketosis, and increased excretion of glucose in the urine developed when tolbutamide was substituted for insulin or was used before insulin therapy was begun. The only serious toxic manifestation observed was a skin rash in two patients. Successful control of diabetes with tolbutamide was limited to cases in which the disease was of mild, stable type and the patient was 40 or more years of age, of normal weight, and with a previous insulin requirement of 5 to 30 units per day. It was of benefit in 43.5 per cent of all diabetic patients in the series studied and in about 75 per cent of the group that might be referred to as selected. The duration of the disease and the duration of insulin therapy were unimportant in predicting effectiveness for tolbutamide therapy.