FORMULATION STUDIES ON TOPICAL PREPARATIONS OF CLONAZEPAM

Within a wide study designed to the development of a transdermal deliv ery system of clonazepam, in the present work the in vitro permeation behaviour of the drug from a series of alcoholic-gel or emulsion-gel f ormulations containing various enhancing agents was investigated. Phys icochemical properties of each gel and drug kinetic permeation paramet ers were determined. The flux of the drug was found to be principally influenced by both the drug solubility in the vehicle and the formulat ion viscosity. The results indicated the great importance of a proper choice of the vehicle for optimization of drug delivery. The formulati ons containing isopropanol gave the best results, yielding a flux of c lonazepam up to four times greater than in the absence of enhancer.