The successful method of replacing human regular insulin with short-acting insulin analog lispro: Treatment with the short-acting insulin analog lispro in variable combination with NPH insulin at mealtime

Objectives To establish the method of replacing human regular insulin (R) with short-acting insulin analog lispro (LP), and to examine the effects of the replacement on postprandial glycemic control. Methods We examined ten diabetic patients who had been treated with intensive insulin therapy. We measured the plasma glucose levels before a 400kcal meal, and 30-, 60-, 90-, 120-, 180-, 240- and 360-min postprandial plasma glucose levels (PPG). R, as well as various doses of LP (100%, 75%, 50% 25% of R dose) were tried before the meal. Various doses of NPH were added with LP before the meal, and the mixing percentages of LP/NPH were 75/ 25, 50/50, 25/75, 0/100. Results PPG was lower in the LP + NPH combination-therapy than that in the R, NPH, LP monotherapy. The PPG was improved most successfully and hypoglycemia was less frequent with the mixing percentage 50/50 or 75/25. Conclusions We concluded that, compared with R and other mixing percentages of LP and NPH, mealtime injection of LP and NPH combination therapies using mixing percentage of 75/ 25 or 50/50 results in better postprandial glucose levels with less frequent hypoglycemia as well.