This medication is a beta-blocker used to treat chest pain (angina), heart failure, and high blood pressure. Lowering high blood pressure helps prevent strokes, heart attacks, and kidney problems.

This drug works by blocking the action of certain natural chemicals in your body (such as epinephrine) that affect the heart and blood vessels. This lowers heart rate, blood pressure, and strain on the heart.

This section contains uses of this drug that are not listed in the approved US professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used for irregular heartbeats or after an acute heart attack to improve survival. It may also be used to reduce the risk of migraine headaches.

See also Warning section.

Take this medication by mouth as directed by your doctor, usually once daily. This medication may be taken with or without food.

Do not crush or chew extended-release tablets. Doing so can release all of the drug at once, increasing the risk of side effects. Also, do not split extended-release tablets unless they have a score line and your doctor or pharmacist tells you to do so. Swallow the whole or split tablet without crushing or chewing.

To reduce your risk of side effects, your doctor may direct you to start this medication at a low dose and gradually increase your dose. Follow your doctor's instructions carefully. The dosage is based on your medical condition and response to treatment.

Use this medication regularly to get the most benefit from it. To help you remember, take it at the same time each day. Do not suddenly stop taking this medication without consulting your doctor. Your condition may become worse when the drug is suddenly stopped.

For the treatment of high blood pressure, it may take several weeks before you get the full benefit of this drug. Keep taking this medication even if you feel well. Most people with high blood pressure do not feel sick.

To prevent chest pain, a second heart attack, or migraine headaches, it is very important to take this medication regularly as prescribed. This drug should not be used to treat chest pain or migraines when they occur. Use other medications to relieve sudden attacks as directed by your doctor (for example, nitroglycerin tablets placed under the tongue for chest pain, "triptan" drugs such as sumatriptan for migraines). Consult your doctor or pharmacist for details.

Tell your doctor if your condition does not get better or if it gets worse (for example, your blood pressure readings remain high or increase, your chest pain or migraines occur more often).

See also Warning section.

Drowsiness, dizziness, tiredness, diarrhea, and slow heartbeat may occur. Decreased sexual ability has been reported rarely. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

To reduce the risk of dizziness and lightheadedness, get up slowly when rising from a sitting or lying position.

With some brands of this medication, an empty tablet shell may appear in your stool. This is harmless.

This drug may reduce blood flow to your hands and feet, causing them to feel cold. Smoking may worsen this effect. Dress warmly and avoid tobacco use.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• very slow heartbeat
• fainting
• blue fingers/toes
• new or worsening symptoms of heart failure (such as shortness of breath, swelling ankles/feet, unusual tiredness, unusual/sudden weight gain)
• mental/mood changes (such as confusion, mood swings, depression)

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking metoprolol, tell your doctor or pharmacist if you are allergic to it; or to other beta-blockers (such as atenolol, propranolol); or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• certain types of heart rhythm problems (such as a slow heartbeat, second- or third-degree atrioventricular block, sick sinus syndrome)
• breathing problems (such as asthma, chronic bronchitis, emphysema)
• liver disease
• serious allergic reactions, including those needing treatment with epinephrine
• blood circulation problems (such as Raynaud's disease, peripheral vascular disease)
• mental/mood disorders (such as depression)
• a certain muscle disease (myasthenia gravis)

This drug may make you dizzy or drowsy. Alcohol or marijuana (cannabis) can make you more dizzy or drowsy. Do not drive, use machinery, or do anything that needs alertness until you can do it safely. Limit or avoid alcoholic beverages. Talk to your doctor if you are using marijuana (cannabis).

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

This product may prevent the fast/pounding heartbeat you would usually feel when your blood sugar level falls too low (hypoglycemia). The risk is higher if you have diabetes, or are vomiting, fasting, or not eating regularly. Other symptoms of low blood sugar level, such as dizziness and sweating, are not affected by this drug.

If you have diabetes, this product may make it harder to control your blood sugar levels. Check your blood sugar levels regularly as directed by your doctor. Tell your doctor right away if you have symptoms of high blood sugar such as increased thirst/urination. Your doctor may need to adjust your diabetes medication, exercise program, or diet.

Children may be at greater risk for low blood sugar (hypoglycemia) while using this drug, especially if they are vomiting or not eating regularly. To help prevent low blood sugar, make sure children eat regularly. If your child cannot eat regularly, is vomiting, or has symptoms of low blood sugar (such as sweating, shaking), tell the doctor right away.

During pregnancy, this medication should be used only when clearly needed. It may harm an unborn baby. Discuss the risks and benefits with your doctor.

This drug passes into breast milk but is unlikely to harm a nursing infant. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

A product that may interact with this drug is:

• fingolimod

Other medications can affect the removal of metoprolol from your body, which may affect how metoprolol works. Examples include lumefantrine, propafenone, quinidine, SSRI antidepressants (such as fluoxetine, paroxetine), St. John's wort, among others.

Some products have ingredients that could raise your heart rate or blood pressure or worsen your heart failure. Tell your pharmacist what products you are using, and ask how to use them safely (especially cough-and-cold products, diet aids, or NSAIDs such as ibuprofen/naproxen).

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669. Symptoms of overdose may include: very slow heartbeat, severe dizziness, severe weakness, fainting, trouble breathing.

Do not share this medication with others.

Talk with your doctor about lifestyle changes that may help this medication work better (such as stress reduction programs, exercise, and dietary changes).

Have your blood pressure and pulse (heart rate) checked regularly while taking this medication. Learn how to check your own blood pressure and pulse at home, and share the results with your doctor.

Lab and/or medical tests (such as liver function) should be done while you are taking this medication. Consult your doctor for more details.

If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).