Biopharmaceutical studies on insulin rectal dosage form . Ⅲ.Bioavailability of insulin suppositories in rabbits by radioimmunoassay.

Insulin suppositories prepared with cocoa butter and 1 % surfactant NO-10 werestudied in rabbits at the dose of 3 IU/kg,and insulin enema was used as a control.The insulin level in blood at given intervals determined by radioimmunoassay was compared with the blood sugar level assayed by Folin-Malmoros method.In the lgG-t figure it is showm that the fatality of the drug in vivo was conformed with the single compartment model in which the peak time (tmax) was 0.5hr, the peak value (Cmax) was 547 IU/ml and the eliminating half-life(t 1/2) was 0.27 hr. The relative bioavailability of insulin suppository was 83%. The time for decreasing the blood sugar level to the minimum was 1.5 hr, while the time for blood insulin concentration peak was 0.5 hr.