Preprandial dosing (within 5 min before meal) and postprandial dosing (15-20 min after meal onset) of NovoLog Mix 70/30 (BIAsp 30, a biphasic formulation of insulin aspart, 30% soluble and 70% protamine-crystallized) were compared in elderly (> or =65 years) type 2 diabetes patients in this open-label, 12-week, crossover study. Ninety-three patients were treated with b.i.d. preprandial injections of BIAsp 30 during a 2-week run-in period and subsequently randomized to a 4-week treatment with either pre- or postprandial b.i.d. BIAsp 30, followed by crossover to the other regimen for 4 weeks. Mean plasma glucose values during a 4-h mealtest at the end of each treatment were similar for pre- and postprandial BIAsp 30 (153 +/- 58 mg/dl and 161 +/- 59 mg/dl, respectively, difference not significant). However, the mean blood glucose increment from self-measured blood glucose values was slightly but significantly greater after postprandial injection than after preprandial injection (treatment difference: 16.3mg/dl; 95% CI: [0.5, 29.3]). Fifty-six percent of patients reported a hypoglycemic episode; postprandial injection did not increase the incidence of hypoglycemia as compared to preprandial injection (113 episodes versus 125 episodes, respectively). For some elderly type 2 diabetes patients, postprandial injection of BIAsp 30 may be an acceptable alternative to standard preprandial injection.