EFFECTS OF FORMULATION VARIABLES ON THE PULMONARY DELIVERY OF INSULIN

The effects of some formulation variables on the pulmonary absorption of insulin in presence of a bile salt, sodium glycocholate (NaGC), hav e been described in this report. Relationship between intratracheally administered insulin dose and pharmacodynamic response has been establ ished. The data obtained from this study revealed that an increase in the viscosity of an aqueous formulation administered to pulmonary sacs can facilitate insulin absorption probably due to reduced mucocilliar y clearance. A hypertonic formulation produced similar overall hypogly cemic effect to the isotonic solution. On the other hand, hypotonicity elicited significantly improved hypoglycemic response, probably due t o membrane damage. The cumulative hypoglycemic effect of intratracheal ly administered insulin has been linearly correlated with the logarith mic doses.