Absorption and miscibility of regular porcine insulin after subcutaneous injection of insulin-treated diabetic patients.

The absorption and miscibility of subcutaneously injected 125I-regular porcine insulin was examined in 20 insulin-treated diabetic patients. The disappearance half-life (t1/2) was 2.1 +/- 0.8 h (SD) after injection of regular insulin (40 U/ml) and 2.3 +/- 0.7 h when mixed with porcine NPH insulin (NS). A significant inverse relation was demonstrated between insulin concentration and absorption, as t1/2 was 1.8 +/- 0.7 h (P less than 0.05) when using 20 U/ml. The interindividual coefficients of variation for absorption of regular insulin were 30.9-41.6% and independent of the presence of NPH insulin. The intrapatient variability, however, was much smaller, 14.5-23.6%.