Flunixin impurities refer to the chemical compounds or substances that may be present in flunixin, a nonsteroidal anti-inflammatory drug (NSAID). These impurities may arise during the manufacturing, storage, or transportation of the drug, and they can affect its purity, potency, and safety. Therefore, it is crucial to identify and quantify these impurities to ensure the quality and efficacy of flunixin in veterinary medicine.