Absorption kinetics and action profiles after sequential subcutaneous administration of human soluble and lente insulin through one needle.

The effects of sequential administration through one needle of human soluble and human lente insulin on plasma insulin levels and action profiles, assessed with glucose clamping, were studied in six healthy volunteers. Insulin kinetics after administration of human soluble insulin (0.22 IU/kg) alone were compared with those after sequential administration of 1) human soluble insulin followed by human lente insulin and 2) human lente insulin followed by human soluble insulin. Total insulin dose in both sequences was 0.55 IU/kg, 40% of which was short-acting insulin. Plasma insulin levels were not significantly different at any time point between 0 and 240 min after soluble insulin compared with either combination. Although insulin levels were slightly but significantly lower at 30 and 105 min after lente followed by soluble insulin compared with soluble followed by lente insulin, these differences probably reflect chance occurrences. Glucose requirements were not significantly different after either of the three administrations. We therefore conclude that the unwanted retarding effect after mixing of human soluble insulin with human lente insulin in the syringe on the onset of action of the soluble insulin can be prevented by sequential subcutaneous injection of these insulins with two syringes through one needle.