Evaluation of Bioavailability upon Oral Administration of Cinnarizine-[beta]-Cyclodextrin Inclusion Complex to Beagle Dogs

The bioavailability of cinnarizine (CN) upon oral administration of its β-cyclodextrin complex to beagle dogs was investigated in comparison with that of CN alone. The dissolution rate at pH 3.0-6.8 was increased significantly by inclusion complexation, but there was no difference in the bioavailability of CN after oral administration of β-cylodextrin complex and that of CN alone. The absorption of CN was decreased significantly when CN was administered with NaHCO3. However, no decrease was observed in the case of CN-β-cylodextrin inclusion complex.