Evaluation of Celecoxib-Lactose Incompatibility Reactions at Solid State using Physicochemical Methods

Background & Aims : Drug excipient incompatibility evaluation is an important part of pre-formulation studies. Drug-excipient interaction may affect drug stability, bioavailability, therapeutic effects, efficacy, and safety. Therefore, development of a successful drug delivery systems or dosage forms depends on correct selection of excipients. The aim of this study is to evaluate of celecoxib-lactose incompatibility reactions at solid state using physicochemical methods. Materials & Methods: Celecoxib and lactose were blended in 1:1 mass ratios and added to 20% (v/w) water and stored in closed vials at 60°C (inside the oven). Also, pure drug and pure excipient were prepared. Celecoxib, celecoxib-lactose and lactose tablets prepared using direct compression method. Produced tablets were stored at 60 °C (inside the oven). Finally, celecoxib -lactose incompatibility in the solid state was investigated by Fourier transform infrared (FTIR) and differential scanning calorimetry (DSC) methods over four consecutive weeks. Results : the incompatibility of celecoxib with lactose was not observed using physicochemical methods including DSC, FTIR spectroscopy and also visual observation. Conclusion: It can be concluded that using lactose in celecoxib solid pharmaceutical preparations will not cause incompatibilities.