NASAL ABSORPTION OF ROXITHROMYCIN FROM GEL PREPARATIONS IN RABBITS

Abstract

Gel preparations of roxithromycin prepared with polymers such as sodium carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl-methyl cellulose (HPMC) and carbopol-polyethylene glycol (PEG), were administered into the nasal cavity of rabbits. Besides, a nasal aqueous suspension of roxithromycin was also applied. The results were compared with oral and intravenous administrations. The bioavailability of the roxithromycin gel formulation prepared with CMC was almost identical to that of the i.v. route and it decreased in the order of HEC, HPMC and carbopol-PEG. Although the dose of roxithromycin in each nasal formulation was 40% of the commercial tablet form, nasal administration was superior to that of the oral route for all three gel formulations except the one with carbopol-PEG. This study carried out on rabbits shows that with a nasal application of roxithromycin-CMC gel preparation, a 95% bioavailability can be attained and the single dose of the commercial tablet can be reduced by 60%.