INVITRO RELEASE STUDIES OF CHLORPHENIRAMINE MALEATE FROM TOPICAL BASES USING CELLULOSE MEMBRANE AND HAIRLESS MOUSE SKIN

In-vitro release of chlorpheniramine maleate from various dermatological bases including a polymeric gel base, the modified hydrophilic base and the modified hydrophilic petrolatum base, was studied. The additive ingredients known to enhance the drug release from the topical bases were also evaluated at different concentration levels. These included urea, ethanol and dimethylsulfoxide (DMSO). The rank order of drug release through the cellulose membrane was observed to be: the gel base > the modified hydrophilic base > the modified hydrophilic petrolatum base. In general, the presence of the additives adversely affected the drug release except for the (DMSO) and ethanol in certain cases. The formulations with optimum in-vitro release profiles of the drug through the cellulose membrane, were selected for further studies of the drug release using hairless mouse skin as the diffusion barrier. Here again, the gel formulation gave the best in-vitro release of the drug, and the data correlated well with the results previously obtained from the cellulose membrane. The in-vitro data were treated with various kinetic principles to determine the relevant parameters, such as the steady state flux, the diffusion coefficient and the permeability coefficient. Using these information, the formulations were evaluated for their suitability for delivering chlorpheniramine maleate via the diadermatic dosage form.