Formulation Evaluation and Kinetic Studies of Etodolac Delayed Release Tablets Using Optimized Solid Dispersion

Abstract

Rheumatoid arthritis is a chronic autoimmune inflammatory disease of the connective tissue in the synovial joints characterised by pain, stiffness, swelling of joints with impaired movement and disability. The symptoms of the disease are severe in the morning hours. The severity of rheumatoid arthritis can be reduced by chronotherapy, which involves the administration of dosage form in correct time to achieve the maximum plasma concentration of the drug available in the early morning hours. The objective of the present study was to develop delayed release tablets of etodolac using optimized formulation of solid dispersion by using response surface methodology based on 32 factorial design. The delayed release tablets contain solid dispersions of etodolac as a carrier, using the polymers like ethyl cellulose (EC), eudragit S100 (ER S100) and polyvinyl payroll done K 30(PVP) for the controlled drug release. The prepared solid dispersion along with tablet excipients were compressed into tablet using rotary tablet press. The formulated tablets were evaluated for recompression, post compression parameters and in vitro dissolutions studies were also performed. There was no drug release in the gastrointestinal pH 1.2, after a programmed lag time and thus it is suitable for chromo the rape tic drug delivery. The release pattern of the formulated tablets were evaluated for its release mechanism and the data was plotted according to zero order, higuchi model, first order kinetics and korsmeyer - peppas model. The drug was released from the matrix tablets following zero order kinetics, indicates the non fickian anomalous diffusion. The above results supports that formulated tablets is used as a successful dosage form for the chromo the rapeutic delivery of etodolac for the relief of symptoms of arthritis and also to overcome the gastric disturbances.