Nasal absorption of propranolol from different dosage forms by rats and dogs.

The blood levels of propranolol in rats and dogs were compared after the administration of nasal, intravenous, and oral solutions. The results indicate that the blood drug levels after nasal and intravenous administration were identical, but the oral administration resulted in considerably lower blood levels. Sustained-release formulations of the drug also were administered nasally and resulted in low initial but prolonged blood levels. The bioavailability of the sustained-release formulation was identical to that of the intravenous administration.