The Effect of Tablet Formulation and Hardness on in Vitro Release of Cephalexin from Eudragit L100 Based Extended Release Tablets

Eighteen batches of cephalexin extended release tablet were prepared by wet granulation method by using Eudragit L100. The effect of the concentration of Eudragit L100, microcrystalline cellulose and tablet hardness on cephalexin release was studied. The formulated tablets were also characterized for physical and chemical parameters. The dissolution results showed that a higher amount of Eudragit in tablet composition and higher tablet hardness resulted in reduced drug release. An increased amount of microcrystalline cellulose in tablet composition resulted in enhanced drug release. Tablet composition of 13.3% w/w Eudragit L100 and 6.6 to 8% w/w microcrystalline cellulose with hardness of 7—11 kg/cm2 gave predicted release for 6 h. The in vitro release was compared with a marketed tablet. Physical and chemical parameters of all formulated tablets were within acceptable limits. The effect of storage on in vitro release and physicochemical parameters of tablets was evaluated and two batches among formulated eighteen batches found to be in acceptable limits.