Absorption from the nasal mucous membrane. I. Nasal absorption of hydralazine in rats
Kaneo, Y.
Acta Pharmaceutica Suecica 20(5): 379-388
1983
ISSN/ISBN: 0001-6675 PMID: 6666600 Accession: 004649493
Hydralazine [an antihypertensive] was well absorbed through the nasal mucosa in rats. The in situ recirculation experiment indicated that the classical partition theory could not be applied to the pH profile of the drug absorption. An asymptotic minimum absorption at pH .mchlt. pKa of the basic drug suggested that the aqueous channel is one of the important pathways of drug transport across the nasal mucosa. In in vivo experiments, a good availability was obtained following the nasal administration of saline solution of hydralazine HCl (pH 3.0). The absorption rate observed was relatively slow. Adding a surfactant or adjusting the pH to neutral significantly enhanced the nasal absorption of hydralazine.