Displaying 2 results of Penbutolol Impurities Penbutolol is a beta-blocker medication used to treat hypertension and angina. It works by slowing down the heart rate and reducing the workload on the heart. However, like all medications, penbutolol may contain impurities that can affect its efficacy and safety. These impurities can be caused by various factors such as manufacturing processes, storage conditions, and degradation over time. Therefore, it is important to ensure the purity and quality of penbutolol to ensure its effectiveness and minimize potential side effects.