In vivo studies on nasal preparations of ciprofloxacin hydrochloride.

Gel formulations of ciprofloxacin hydrochloride (CPH) were prepared with bioadhesive polymers such as hydroxypropyl methylcellulose (HPMC), hydroxyethyl cellulose (HEC) and methylcellulose (MC). They were administered into the nasal cavity of rabbits. A nasal aqueous suspension of CPH with glycerol was also applied. In addition, the effect of Tween 80 as penetration enhancer was examined. The agar plate diffusion technique was applied for the assay of CPH. The results were compared with oral and intravenous administrations. The bioavailability of the CPH gel formulation prepared with HPMC was almost identical to that of the oral route. Other nasal formulations with HEC and MC had bioavailabilities lower than oral preparations. The relative bioavailabilities for the formulation containing HEC and MC were 48.7 and 45.54%, respectively. To increase the bioavailabilities, 1% (w/w) of Tween 80 was added. The bioavailability of these gel formulations increased to 63.54 and 55.72%, respectively. Experiments carried out on rabbits showed that the nasal administration of CPH bioadhesive gel formulation containing HPMC may be an alternative to the oral route.