Simultaneous Determination of Aspirin and Cilostazol in Fixed-dose Tablet Formulation Using High-performance Liquid Chromatography

Stroke and myocardial infarction remain to be the top causes of morbidity and mortality in the Philippines. Medical practitioners usually prescribe a cocktail of drugs to prevent and manage these conditions. Among these medications are aspirin and cilostazol, both belong to the class of antiplatelet drugs. These drugs prevent the aggregation of platelets resulting in the formation of clots and obstruction in the blood vessels. These medications are available in separate dosage forms, and no fixed-dose combinations (FDCs) are available in the market. In this study, high- performance liquid chromatography was used in assessing the compatibility of aspirin and cilostazol as an FDC using a developed method. Results showed that there are no alterations of both aspirin and cilostazol, with 90–110% recovery that follows the guidelines for accuracy; for precision, both aspirin and cilostazol have an average of 1.97 and 1.70% relative standard deviation (RSD), and correlation coefficient of not less than 0.990 for the linearity. The LOD and LOQ were also within the specification with 0.0474 and 0.1436 mg/L for aspirin and 0.0479 and 0.1452 mg/L for cilostazol, respectively. A less than 5% RSD for the robustness of both drugs was calculated indicating that the two drugs are compatible and can be formulated into an FDC, thereby providing more options for clinicians and patients in managing these conditions.