THE DISTRIBUTION OF AN INTRANASAL INSULIN FORMULATION IN HEALTHY-VOLUNTEERS - EFFECT OF DIFFERENT ADMINISTRATION TECHNIQUES

The initial deposition pattern in the nasal passages and subsequent cl earance of an insulin formulation labelled with Tc-99m-human serum alb umin have been determined in 12 healthy male volunteers. Four differen t administration modes from a novel aqueous spray device were compared , involving delivered volumes of 80-160 mu L, and with either gentle o r vigorous inhalation while firing the device. The entire dose was dep osited in the nasal cavity, and no significant radioactivity was depos ited in the lungs. A mean 25-33% of the radiolabel remained ih the nos e after 4 h. A significantly smaller area of the nasal mucosa was cove red by the smallest (80 mu L) bolus, but subsequent clearance rates di d not vary significantly with mode of administration. Blood glucose le vels fell after administration of the insulin formulation, but no seri ous episodes of hypoglycaemia occurred.