Metoprolol is used to treat angina (chest pain) and hypertension (high blood pressure). Learn about side effects, interactions and indications. Metoprolol Tablets Metoprolol (Lopressor®) is a medication that lowers your blood pressure and heart rate, making it easier for your heart to pump blood to the rest of your body. It treats high blood pressure. It also prevents chest pain or further damage after a heart attack. It’s a type of beta-blocker. Get more information about metoprolol, include how it works, what it can be used for, and what to expect when taking the medication. A 50 mg dose of immediate release metoprolol t.i.d. produced a peak plasma level of metoprolol similar to the peak level observed with 200 mg of metoprolol succinate extended-release. Easy-to-read patient tips for metoprolol covering how it works, benefits, risks, and best practices. Metoprolol may worsen the symptoms of heart failure in some patients. Check with your doctor right away if you are having chest pain or discomfort, dilated neck veins, extreme fatigue, irregular breathing or heartbeat, swelling of the face, fingers, feet, or lower legs, trouble breathing, or weight gain. Find patient medical information for Metoprolol (Lopressor, Toprol XL, others) on WebMD including its uses, side effects and safety, interactions, pictures, warnings, and user ratings Metoprolol belongs to a class of drugs known as beta blockers. It works by blocking the action of certain natural substances in your body, such as epinephrine, on the heart and blood vessels. Metoprolol is a prescription medication used to treat the symptoms of Hypertension, Acute Myocardial Infarction, Congestive Heart Failure, Angina. Learn about side effects, dosages, drug interactions, and more. Read on to learn about the side effects of metoprolol, including common, severe, and long-term side effects, and how to manage them.