Formulation and evaluation of novel orodispersible tablet by drug-drug solid dispersion of metoprolol tartrate and hydrochlorothiazide

This study investigates the effect of a novel drug-drug solid dispersion approach on the dissolution of hydrochlorothiazide in a fixed-dose combination with metoprolol tartrate. Solid dispersions of hydrochlorothiazide and metoprolol tartrate (12.5 mg: 25 mg) were prepared using the solvent evaporation technique. These dispersions were characterized by differential scanning calorimetry (DSC), Fourier-transform infrared spectroscopy (FTIR). The prepared solid dispersions, along with selected excipients, were compressed into orodispersible tablets and evaluated for precompression and post compression parameters. The solubility of hydrochlorothiazide was observed to increase with the concentration of metoprolol tartrate, as demonstrated by phase solubility studies and comparative solubility studies. Stability studies on the tablets indicated no significant changes in disintegration time, dissolution profile, or overall stability. The findings of this study suggest that the novel drug-drug solid dispersion approach is promising for enhancing the dissolution of poorly soluble drugs, when combined with soluble drugs in fixed-dose combinations.