Easy-to-read patient tips for metoprolol covering how it works, benefits, risks, and best practices. Get more information about metoprolol, include how it works, what it can be used for, and what to expect when taking the medication. 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. Read on to learn about the side effects of metoprolol, including common, severe, and long-term side effects, and how to manage them. 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. 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 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. 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. Metoprolol is used to treat angina (chest pain) and hypertension (high blood pressure). Learn about side effects, interactions and indications. Metoprolol is used to treat high blood pressure, angina (chest pain) and heart failure. Metoprolol also is used to improve survival after a heart attack. Metoprolol is in a class of medications called beta blockers. It works by relaxing blood vessels and slowing heart rate to improve blood flow and decrease blood pressure.