Icatibant is a medication used to treat hereditary angioedema. However, as with all pharmaceuticals, it is not 100% pure and may contain impurities. These impurities may be residual solvents, degradation products or other unknown substances. It is important to identify and control these impurities to ensure the safety and efficacy of the medication. Analytical techniques such as HPLC and LC-MS are commonly used to detect and quantify icatibant impurities.