• Carbutamide, a sulfonamide derivative, has been administered to 31 diabetic patients. Given by mouth, it was found to be absorbed rapidly and excreted slowly, so that satisfactory responses were achieved with maintenance doses of 1 gm. per day. Attempts were made to maintain a level of at least 10 mg. per 100 cc. of blood. Reduction of hyperglycemia was accomplished with carbutamide alone in some cases. In other cases, the carbutamide reduced the insulin requirement. It was not satisfactory in young persons with unstable diabetes or in the emergency treatment of diabetics in acidosis. Side-effects that occurred in one case were temporary. The effectiveness of orally administered carbutamide in lowering the blood sugar level indicated that it should be useful in many cases of mild or moderately severe diabetes.