Enhancement of Solubility and Dissolution Rate of Telmisartan and Hydrochlorothiazide by Solid Dispersion Technique

Abstract

Drugs having poor aqueous solubility present one of the major confronts better absorption for good bioavailability of such drugs. The objective of this research was to increase the solubility, drug dissolution and to enhance the bioavailability of low aqueous soluble drugs Telmisartan and hydrochlorothiazide by solid dispersion technique. Solid dispersion of Hydrochlorothiazide and Telmisartan in a fixed dose combination was prepared. The major problem with these drugs both drugs are BCS class II drug having very low water solubility that resulting in poor bioavailability after oral administration. SD formulation of both drug Telmisartan and hydrochlorothiazide was prepared by using two different carrier like PEG 6000 and Gelucire 50/13 in 1:1, 1:3, 1:5 and 1:7 drug to polymer ratio by solvent evaporation method & it is evaluated by FTIR, X-ray diffraction and DSC analyses and in-vitro dissolution characteristics. The results showed reduction in particle size, change from crystalline form to amorphous form and enhanced the dissolution rate of hydrochlorothiazide from solid dispersion as compared to physical mixture as well as pure hydrochlorothiazide. The findings of the present study propose that the novel drug-drug solid dispersion approach is beneficial for fixed dose combinations of poorly soluble and soluble drugs to improve bioavailability of poorly soluble drugs.