Albendazole (ABZ) is a benzimidazol (BZD) derivative with broad spectrum of activity againstrnhuman and animal helminth parasites. However, its poor water solubility gives rise tornformulation problems and reduced bioavailability. These problems can be reduced by increasingrnthe dissolution rate of the drug using different approaches such as solid dispersions (SDs).rnThis study was designed to formulate ABZ loaded SDs with improved dissolution profiles. Forrnthis purpose, binary and ternary SDs were prepared by kneading and solvent evaporationrnmethods using the hydrophilic carriers such as polyethylene glycol 4000 (PEG), polyvinylrnpyrrolidone K-30 (PVP) and hydroxypropyl methylcellulose 5 cps (HPMC) and the surfactantrnpolysorbate 80. To prepare binary SDs, the carriers were used in three drug: carrier proportionsrn(1:0.5, 1:1, 1:2), where as in case of ternary SDs, polysorbate 80 was added at 0.1 proportion ofrnthe pure drug for all proportions of the carriers used. Physical mixtures (PMs) containing thernabove mentioned carriers were similarly prepared for comparison purpose.rnFourier Transformer Infrared Spectroscopy (FTIR) studies of the samples stored for 2 monthsrnrevealed interaction through hysdrogen bonding between the drug and the carriers. DifferentialrnScanning Calorimetry (DSC) of the PMs and SDs indicated decreased crystallinity of the drug.rnDissolution profiles of ABZ were remarkably improved from the binary and ternary SDs as wellrnas from ternary PMs than the pure drug (4.50% within 60 min). The rate and extent ofrndissolution was significantly higher in the ternary systems than the binary systems (p < 0.5).rnSolvent evaporation method demonstrated the highest dissolution profile. The ternary SD ofrnABZ with PEG and polysorbate 80 at a ratio of 1:2:0.1 prepared with solvent evaporationrntechnique showed the highest dissolution profile with 100% of the drug released within 60 min.rnThe SDs with PEG showed higher dissolution profiles than with PVP in both the SDs preparedrnby kneading and solvent evaporation techniques. From the SDs prepared by kneading method,rnthe highest drug release was observed with the carrier HPMC (88.8% of the drug being releasedrnwith 60 min) followed by PEG (81.4%). In all the formulations the release of ABZ was shown tornincrease with increasing carrier proportions.rnXIIIrnThe prepared SDs were characterized for flow properties and compressibility. Tablets of selectedrnSDs were prepared by direct compression method and evaluated for their quality attributes. Thernresults revealed that the major factors that affect the SDs and tablet characteristics are carrier torndrug ratio, the amount of microcrystalline cellulose (MCC) and compression force. Thus, 3rnfactors, two level (2 3) full factorial experimental design was selected to investigate the effects ofrnthe selected factors on the various responses such as flow property, compressibility and drugrnrelease in 10 min and 60 min. Accordingly, the various models describing the relationship of thernselected variables were obtained using Design-Expert 9.0.6 software and the optimum area wasrndetermined. The optimal points for the responses were found to be 55.09% for amount of ABZrnreleased within 10 min, 81.27% for amount of ABZ released within 30 min, 29.48Â° for angle ofrnrepose, 94.60 N for hardness and 0.62% for friability when the factors are set at compressionrnforce of 14.03 KN, carrier to drug ratio of 1.98 and concentration of MCC of 23.57%. Thernvalidity of obtained optimal point was confirmed experimentally. Evaluation of the optimizedrnformulation showed successful formulation of ABZ SD tablets. The release profiles of thernoptimized tablet formulation were superior to marketed tablets. Thus, it can be concluded that therndissolution of ABZ is significantly enhanced by SD technique.rnKey Words: Albendazole; HPMC; Kneading; PEG; Physical mixture; Polysorbate 80; PVP;rnSolid dispersion; Solvent evaporation