Research has established the importance of maintaining blood glucose levels near normal in patients with type 1 (insulin-dependent) diabetes mellitus. Short-acting insulin analogs are designed to overcome the limitations of regular short-acting insulins. Compared with regular human insulin, the analog insulin lispro offers faster subcutaneous absorption, an earlier and greater insulin peak and a more rapid postpeak decrease. Insulin lispro begins to exert its effects within 15 minutes of subcutaneous administration, and peak levels occur 30 to 90 minutes after administration. Duration of activity is less than five hours. Rates of insulin allergy, lipodystrophy, hypoglycemia and abnormal laboratory test results are essentially the same in patients using insulin lispro and in those using regular human insulin.