Metoprolol is a beta-blocker medication used to treat high blood pressure, angina, and other cardiovascular conditions. There are several other names for this medication available in the market. Lopressor, Metoprolol Succinate ER, Toprol-XL, and Betaloc are some of the synonyms for Metoprolol. These names refer to the same medication with the same active ingredient, but some of them might come in different formulations or different dosages. If you are taking metoprolol, it is essential to stick with one of these names as prescribed by your doctor. It is also important to note that different generic versions of metoprolol may have slightly different formulations, so it is essential to follow your doctor's instructions for taking this medication.