Morphologic examination of rabbit nasal mucosa after the nasal administration of insulin peanut oil suspension and a powder dosage form with soybean-derived sterylglucoside.

Soybean-derived sterylglucoside mixture (SG) is a potentially effective absorption enhancer for the nasal absorption of insulin. Insulin is a peanut oil suspension dosage form and in a powder dosage form with SG were administered into the rabbit nasal cavity. After 0.5 or 1 h, nasal mucosa was taken from the nasal cavity and side effects were examined by an optiphoto light microscope. The insulin in the peanut oil suspension produced a histological change in the nasal epithelium mucosae, as well as mucodermal phlogistic cellular infiltration. The peanut oil suspension with SG showed side effects slightly stronger than without SG. SG alone and the insulin powder dosage form with SG produced no signs of inflammation, erosion or squamous metaplasia. The results from this study indicate that SG can be considered safe.