SYSTEMIC ABSORPTION OF INSULIN AND GLUCAGON APPLIED TOPICALLY TO THE EYES OF RATS AND A DIABETIC DOG

Nondiabetic rats were anesthetized with xylazine/ketamine to induce hy perglycemia and systemic insulin absorption from eyedrops formulated w ith dodecylmaltoside was quantitated by both a decrease in serum level s of D-glucose and an increase in immunoreactive insulin levels. When insulin eyedrop administration was delayed until 60 minutes after the administration of eyedrops containing 0.25% dodecylmaltoside, the enha nced systemic absorption of insulin was maintained, suggesting that do decylmaltoside had an effect directly on the permeability of the nasal sinus epithelium. When glucagon was formulated in eyedrops or nosedro ps containing dodecylmaltoside, systemic absorption of glucagon could be measured in the form of an increase in the serum D-glucose concentr ation following nasal application, but not after ocular application. E yedrops containing insulin plus 0.125% dodecylmaltoside were administe red to a diabetic dog; a dose of 20 units of regular insulin caused a modest decrease in serum D-glucose concentration and a concomitant inc rease in serum immunoreactive insulin content. These results provide e vidence that peptide drugs such as insulin can be formulated in eyedro ps with low concentrations of dodecylmaltoside, a mild nonionic surfac tant.