Stability of Tranexamic Acid Mouth Rinse

Tranexamic acid is an antifibrinolytic agent that inhibits the conversion of plasminogen to plasmin and is used to treat fibrinolytic hemorrhages. Tranexamic acid mouth rinse was compounded using active pharmaceutical ingredient powder or commercial tablets. The bitter taste was masked by using either cherry-vanilla or peppermint and mint flavoring and aspartame. Tranexamic acid mouth rinse solutions were stored at either 23°C or 5°C in polyethylene terephthalate bottles for 31 days. Stability was accessed using a stability-indicating high-performance liquid chromatographic method. Color, clarity, caking, resuspendability, and pH were also monitored. All solutions remained above 97.2% of the initial concentrations after 31 days storage at either 23°C or 5°C and protected from light. The powder-based solutions remained clear, and no color change was observed. However, some of the tablet formulations stored at 23°C turned yellow to dark brown after 21 days. Insoluble material from the tablet formulations settled out but was easy to resuspend with no caking. The pH of the tranexamic acid mouth rinse solutions changed slightly over the course of the study. All tranexamic acid mouth rinse solutions were chemically stable for 31 days when stored at either 23°C or 5°C and protected from light.