Solubility & Dissolution Enhancement of Antihypertensive Agent(S) using Solid Dispersion Techniques

Drugs having poor aqueous solubility present one of the major confronts better absorption for good bioavailability of such drugs. Solid dispersion of Hydrochlorothiazide and valsartan (12.5 mg : 80 mg) in a fixed dose combination was prepared. The major problem with these drugs is their low aqueous solubility, which results into poor bioavailability after oral administration. The purpose of this study was to prepare and characterize solid dispersions of the poorly water soluble antihypertensive agents Hydrochlorothiazide and valsartan with water soluble carriers such as PEG-6000, Urea, and PVP K-30 to improving its aqueous solubility and rate of dissolution. The solid dispersions of drug were prepared by solvent evaporation technique, fusion method, & co-grinding methods. The observed results showed the solid dispersion of drug were found increased in aqueous solubility than pure drug. Evaluation of the dispersions were performed using aqueous solubility and dissolution studies, the results obtained showed that the aqueous solubility and rate of dissolution of fixed dose combination hydrochlorothiazide and valsartan was significantly improved when formulated in solid dispersions as compare to pure drugs.