Formulation and Evaluation of Floating Oral In-Situ Gel of Etodolac: A Comprehensive Review

Etodolac is a non-steroidal anti-inflammatory drug (NSAID) used for the management of pain and inflammatory disorders. Although conventional oral administration provides effective systemic exposure, the relatively short terminal half-life and rapid gastrointestinal transit may necessitate repeated administration and may produce fluctuating drug concentrations. Gastroretective drug delivery systems (GRDDS), particularly floating oral in-situ gels, provide an attractive approach for prolonging gastric residence and regulating drug release. This review and experimental framework focus on the development of a floating oral in-situ gel of etodolac using suitable hydrophilic and ion-responsive polymers. The formulation is designed to remain in the stomach by generating a low-density, gelled structure following contact with gastric fluid. Sodium alginate, gellan gum, hydroxypropyl methylcellulose (HPMC) and suitable gas-generating agents can be investigated to achieve rapid gelation, adequate floating ability, appropriate viscosity and sustained drug release. Important formulation and evaluation parameters include appearance, pH, viscosity, gelation characteristics, floating lag time, total floating duration, drug content, swelling, in-vitro dissolution, release kinetics and stability. Optimization of polymer concentration and polymer combinations is essential because viscosity, gel strength, buoyancy and drug diffusion are interdependent. A well-designed etodolac floating in-situ gel may provide prolonged gastric residence and controlled drug delivery, although in-vivo gastric-retention and pharmacokinetic studies are required to establish its clinical advantage.