The aim of the present study was solubility and dissolution rate enhancement of diacerein by using different solid dispersion techniques. Solid dispersion of diacerein was prepared by kneading and solvent evaporation method. Solid dispersions of diacerein with PEG-6000, guar gum and poloxamer-188 were prepared in different ratios as 1:1, 1:2, 1:3. FTIR, DSC and XRD were performed to study the interaction between drug and polymers. In solid dispersion formulations there was decrease in crystallinity of diacerein, which leads to increase in dissolution of diacerein from solid dispersions. All methods showed improvement in dissolution profile of diacerein as compare to pure drug. Kneading method shows faster drug release as compared to physical mixture and solvent evaporation method (diacerein and poloxamer -188) this might be due to kneading results in uniform distribution of drug in the polymer and forms the molecular and colloidal dispersion of drug in hydrophilic carrier and reduction of crystallinity of drug. As hydrophilic carrier dissolves, an insoluble drug is exposed to dissolution medium in the form of very fine particles, leading to rapid dissolution. Moreover other factors such as absence of aggregation and/or reagglomeration phenomenon during dissolution and particle size reduction could be attributed to a better dissolution profile.
