Abstract
In vitro release of betamethasone (BeM) from ointment bases containing BeM or its β- and γ-cyclodextrin (β- and γ-CyD) complexes was investigated by using an ointment release simulator with artificial double-layer membranes. The release of BeM from gel and hydrophilic ointments was significantly improved by CyD complexation, owing to increases in the apparent rates of dissolution and membrane permeation of the drug. The enhanced release of BeM from the two ointments may be attributed to the faster dissolution of the complex and the lower binding affinity of the complex to the ointment bases. The present data suggest that an improvement of topical bioavailability of BeM can be obtained by means of inclusion complexation.
