1. Metoprolol oral tablet is available as generic drugs and as brand-name drugs. Brand names: Lopressor and Toprol XL.
  2. Metoprolol comes as immediate-release and extended-release tablets, and an extended-release capsule. It also comes in an injectable form that’s only given by a healthcare provider.
  3. Metoprolol is a drug called a beta-blocker. It’s used to treat conditions such as high blood pressure, heart failure, and angina (chest pain).

Metoprolol is a prescription drug. It comes as immediate-release and extended-release oral tablets, and extended-release oral capsules. It also comes in an injectable form that’s only given by a healthcare provider.

Metoprolol oral tablets are available as the brand-name drugs Lopressor and Toprol XL. They’re also available as generic drugs. Generic drugs usually cost less than the brand-name versions. In some cases, they may not be available in all strengths or forms as the brand-name drugs.

The two brand-name forms of metoprolol (as well as the different generic forms) are different versions of the medication. They’re both metoprolol, but they contain different salt forms. Lopressor is metoprolol tartrate, while Toprol-XL is metoprolol succinate. The different salt forms enable the drugs to be used to treat different conditions.

Metoprolol succinate is an extended-release version of metoprolol, so it remains in your bloodstream for a longer time. Metoprolol tartrate is an immediate-release version of metoprolol.

Why it’s used

Both forms of metoprolol — metoprolol tartrate (Lopressor) and metoprolol succinate (Toprol-XL) — are used to:

However, metoprolol tartrate is also used to treat and prevent heart attacks, while metoprolol succinate is also used to treat heart failure.

Metoprolol may be used as part of a combination therapy. That means you may have to take it with hydrochlorothiazide or chlorthalidone.

How it works

Both versions of metoprolol belong to a class of drugs called beta-blockers. A class of drugs is a group of medications that work in a similar way. These drugs are often used to treat similar conditions.

Blood pressure is often raised because blood vessels are tightened. This puts a strain on the heart and increases the body’s oxygen demand.

Beta-blockers work by preventing norepinephrine (adrenalin) from acting on beta receptors in blood vessels and in the heart. This causes blood vessels to relax. By relaxing the blood vessels, beta-blockers help to lower the heart rate and decrease the heart’s demand for oxygen. This in turn helps decrease blood pressure and reduce chest pain.

Metoprolol oral tablet can cause certain side effects.

More common side effects

The more common side effects that can occur with metoprolol include:

  • tiredness
  • dizziness
  • diarrhea
  • constipation
  • breathing problems such as shortness of breath, cough, and wheezing
  • bradycardia (heart rate that’s slower than normal)
  • reduced interest in sex
  • rash

If these effects are mild, they may go away within a few days or a couple of weeks. If they’re more severe or don’t go away, talk to your doctor or pharmacist.

Serious side effects

Call your doctor right away if you have serious side effects. Call 911 if your symptoms feel life-threatening or if you think you’re having a medical emergency. Serious side effects and their symptoms can include the following:

  • Low blood pressure (hypotension). Symptoms can include:
    • severe dizziness
    • lightheadedness
    • fainting
  • Cold hands and feet. Symptoms can include
    • hands and feet that are cold and may be painful
  • Very slow heart rate (severe bradycardia)
  • Extreme fatigue. Symptoms can include:
    • feeling more tired than usual
    • tiredness that gets progressively worse each day
  • Serious depression. Symptoms can include:
    • continuous feelings of sadness or anxiety
    • feelings of hopelessness or worthlessness
    • lack of interest in hobbies you once enjoyed
    • eating too much or too little
    • trouble concentrating

Metoprolol oral tablet can interact with other medications, vitamins, or herbs you may be taking. An interaction is when a substance changes the way a drug works. This can be harmful or prevent the drug from working well.

To help avoid interactions, your doctor should manage all of your medications carefully. Be sure to tell your doctor about all medications, vitamins, or herbs you’re taking. To find out how this drug might interact with something else you’re taking, talk to your doctor or pharmacist.

Examples of drugs that can cause interactions with metoprolol are listed below.

Mental health drugs

Taking metoprolol with reserpine and monoamine oxidase inhibitors (MAOIs) may increase or add to the effects of metoprolol. They may also increase lightheadedness or slow your heart rate more. MAOIs can continue to interact with metoprolol for up to 14 days after taking them. Examples of MAOIs include:

  • isocarboxazid
  • phenelzine
  • selegiline
  • tranylcypromine

Heart rhythm drugs

Taking heart rhythm drugs with metoprolol can slow down your heart rate too much. Examples of these drugs include:

  • digoxin
  • quinidine
  • propafenone

Calcium channel blockers

Like metoprolol, these drugs are used to treat high blood pressure and several other heart problems. Combined with metoprolol, calcium channel blockers may slow your heart rate even more. Doctors sometimes use this combination under close supervision.

Examples of calcium channel blockers include:

  • amlodipine
  • diltiazem
  • felodipine
  • isradipine
  • nicardipine
  • nifedipine
  • nimodipine
  • nisoldipine
  • verapamil

Drugs processed in the same way as metoprolol

Drugs used to treat depression and other mood disturbances are processed in your body by the same systems as metoprolol. Using these drugs with metoprolol could increase the levels of metoprolol in your body. Examples of these drugs include:

  • fluoxetine
  • fluvoxamine
  • paroxetine
  • sertraline
  • bupropion
  • clomipramine
  • desipramine
  • chlorpromazine
  • fluphenazine
  • haloperidol
  • thioridazine

Other drugs that are processed in the body the same way as metoprolol include:

  • the antiretroviral ritonavir
  • antihistamines, including diphenhydramine
  • antimalarial drugs, such as hydroxychoroquine and quinidine
  • antifungal drugs, such as terbinafine
  • the blood pressure drug hydralazine

These drugs can all increase the level of metoprolol in the body.

Alpha-blockers

Alpha-blockers also lower blood pressure. They may decrease blood pressure too much when combined with metoprolol. Examples of these drugs include:

  • reserpine
  • alpha-methyldopa
  • clonidine
  • prazosin

Clonidine must be carefully managed if it’s combined with metoprolol. Stopping the drug suddenly while also taking metoprolol can cause a big jump in blood pressure.

Ergot alkaloids

Ergot alkaloids, such as dihydroergotamine, narrow blood vessels to treat headaches. If you take them at the same time as metoprolol, they may cause dangerous narrowing of blood vessels.

Dipyridamole

Dipyridamole is used for heart testing. Because metoprolol affects your heart rate, you should stop taking it before you’re given dipyridamole to help ensure an accurate test result.

All possible dosages and forms may not be included here. Your dosage, form, and how often you take the drug will depend on:

  • your age
  • the condition being treated
  • how severe your condition is
  • other medical conditions you have
  • how you react to the first dose

Dosage for high blood pressure

Generic: Metoprolol

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 25 mg, 37.5 mg, 50 mg, 75 mg, and 100 mg
  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Brand: Lopressor

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 50 mg and 100 mg

Brand: Toprol XL

  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Adult dosage (ages 18–64 years)

Immediate-release tablets

  • Typical starting dosage: 100 mg daily in a single or divided doses. This may be gradually increased if needed.
  • Typical maintenance dosage: 100–450 mg per day.
  • Maximum dosage: 450 mg per day.

Extended-release tablets

  • Typical starting dosage: 25–100 mg daily in a single dose. This may be gradually increased if needed.
  • Maximum dosage: 400 mg per day.

Child dosage (ages 6–17 years)

Extended-release tablets

  • Typical starting dosage: 1 mg/kg once daily (maximum initial dose should not exceed 50 mg once daily). This dosage may be gradually increased if needed.
  • Maximum dosage: 2 mg/kg (or 200 mg) once daily.

Immediate-release tablets

These tablets are not approved for use in this age group.

Child dosage (ages 0–5 years)

Dosage for people younger than 6 years hasn’t been established.

Senior dosage (ages 65 years and older)

Your body may process this drug more slowly. Your doctor may start you on a lowered dosage so that too much of this drug does not build up in your body. Too much of the drug in your body can be dangerous.

Dosage for angina (chest pain)

Generic: Metoprolol

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 25 mg, 37.5 mg, 50 mg, 75 mg, and 100 mg
  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Brand: Lopressor

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 50 mg and 100 mg

Brand: Toprol XL

  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Adult dosage (ages 18–64 years)

Immediate-release tablets

  • Typical starting dosage: 50 mg, taken twice a day. This may be gradually increased as needed.
  • Typical maintenance dosage: 100–400 mg per day.
  • Maximum dosage: 400 mg per day.

Extended-release tablets

  • Typical starting dosage: 100 mg taken once a day. This may be gradually increased if needed.
  • Maximum dosage: 400 mg per day.

Child dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior dosage (ages 65 years and older)

Your body may process this drug more slowly. Your doctor may start you on a lowered dosage so that too much of this drug does not build up in your body. Too much of the drug in your body can be dangerous.

Dosage for after a heart attack

Generic: Metoprolol

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 25 mg, 37.5 mg, 50 mg, 75 mg, and 100 mg

Brand: Lopressor

  • Form: immediate-release oral tablet (metoprolol tartrate)
  • Strength: 50 mg and 100 mg

Adult dosage (ages 18–64 years)

Immediate-release tablets

Treatment with this drug is often started in the hospital with the intravenous formulation as soon as possible after a heart attack. Treatment with the oral medication as noted below is begun if your body tolerates the intravenous dosing.

  • Typical starting dosage: 50 mg every 6 hours starting 15 minutes after the last intravenous dose and continuing for 48 hours.
  • Typical maintenance dosage: 100 mg twice daily.

Child dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior dosage (ages 65 years and older)

Your body may process this drug more slowly. Your doctor may start you on a lowered dosage so that too much of this drug does not build up in your body. Too much of the drug in your body can be dangerous.

Dosage for heart failure

Generic: Metoprolol

  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Brand: Toprol XL

  • Form: extended-release oral tablet (metoprolol succinate)
  • Strength: 25 mg, 50 mg, 100 mg, and 200 mg

Adult dosage (ages 18–64 years)

Extended-release tablets

  • Typical starting dosage: For people with NYHA Class II heart failure, it’s 25 mg once daily for 2 weeks. For people with more severe heart failure, it’s 12.5 mg once daily.
  • Typical maintenance dosage: Your doctor can double the dosage every 2 weeks to the highest dosage level your body will tolerate, or up to 200 mg per day.

Child dosage (ages 0–17 years)

Dosage for people younger than 18 years hasn’t been established.

Senior dosage (ages 65 years and older)

Your body may process this drug more slowly. Your doctor may start you on a lowered dosage so that too much of this drug does not build up in your body. Too much of the drug in your body can be dangerous.

Special dosage considerations

For people with liver disease: Liver disease may affect your dosage. Your doctor can tell you more.

Disclaimer: Our goal is to provide you with the most relevant and current information. However, because drugs affect each person differently, we cannot guarantee that this list includes all possible dosages. This information is not a substitute for medical advice. Always speak with your doctor or pharmacist about dosages that are right for you.

FDA warning: Don’t stop taking metoprolol suddenly

  • This drug has a black box warning. This is the most serious warning from the Food and Drug Administration (FDA). A black box warning alerts doctors and patients about drug effects that may be dangerous.
  • Don’t stop taking metoprolol suddenly. If you do, you may experience worse chest pain, a jump in blood pressure, or even have a heart attack. Stopping metoprolol is not recommended. If you need to stop taking the drug, first talk to your doctor. Your dosage should be gradually decreased under a doctor's supervision.

Allergy warning

This drug can cause a severe allergic reaction. Symptoms can include:

  • trouble breathing
  • swelling of your throat or tongue

If you develop these symptoms, call 911 or go to the nearest emergency room.

Don’t take this drug again if you’ve ever had an allergic reaction to it. Taking it again could be fatal (cause death).

Warnings for people with certain health conditions

For people with asthma or COPD: Generally, people with asthma or chronic obstructive pulmonary disease (COPD) shouldn’t take metoprolol. A doctor may still prescribe it, but with careful monitoring. At higher doses, metoprolol can block different receptors on the breathing passages. This narrows the passages, which worsens asthma or COPD.

For people with diabetes: Metoprolol may eliminate tremors and reduce heart rate. Tremors and an increased heart rate are signs of low blood sugar. Without these signals, it becomes more difficult to recognize low blood sugar levels.

For people with poor circulation: If you have poor circulation in your feet and hands, it may become worse when taking metoprolol. Because metoprolol reduces blood pressure, you may get even less blood to these parts of your body.

Warnings for other groups

For pregnant women: Metoprolol is a category C pregnancy drug. That means two things:

  1. Research in animals has shown adverse effects to the fetus when the mother takes the drug.
  2. There haven’t been enough studies done in humans.

If you’re pregnant and have high blood pressure, speak with your healthcare provider about your treatment options during pregnancy.

For women who are breastfeeding: Metoprolol enters the breast milk and could be passed to your baby if you breastfeed while taking this drug. Talk to your healthcare provider before breastfeeding.

For seniors: Seniors may need a smaller dosage of metoprolol at first. The dosage may then increase gradually.

For children: The immediate-release form of the drug has not been established as safe or effective in children. The extended-release form of this drug can be used to treat high blood pressure in children 6 years of age or older.

Metoprolol oral tablet can be used either as a short-term drug or a long-term drug. It comes with serious risks if you don’t take it as prescribed.

If you stop taking the drug or don’t take it at all: You risk:

  • increasing your blood pressure
  • damaging your blood vessels or main organs, such as your lungs, heart, or liver
  • increasing your risk of a heart attack

Also, if you suddenly stop taking metoprolol for high blood pressure, chest pain, or after a heart attack, you raise your risk of heart attack.

If you miss doses or don’t take the drug on schedule: Not taking metoprolol every day, skipping days, or taking doses at different times of day also come with risks. Your blood pressure might fluctuate too often. That might increase your risk for a heart attack.

If you take too much: You could have dangerous levels of the drug in your body. Symptoms of an overdose of this drug can include:

  • severe low blood pressure
  • heart rhythm changes
  • nausea
  • vomiting

If you think you’ve taken too much of this drug, call your doctor or seek guidance from the American Association of Poison Control Centers at 800-222-1222 or through their online tool. But if your symptoms are severe, call 911 or go to the nearest emergency room right away.

What to do if you miss a dose: If you miss a dose, just take the next dose as planned. Don’t double your dose.

How to tell if the drug is working:

  • For high blood pressure or heart failure: You may not be able to tell if this drug is working. Your doctor can do tests to determine if the drug is helping to treat your condition.
  • For angina: Your chest pain should be reduced.

Keep these considerations in mind if your doctor prescribes metoprolol oral tablet for you.

General

  • Take metoprolol with food. This drug may cause nausea. Taking it with food will allow your stomach to digest it better. Take it either with a meal or right after a meal.
  • Don’t crush the extended-release tablet. However, you can cut the tablet along the score marks (the groove on the tablet) if your doctor recommends a smaller dose.
  • You can cut the immediate-release tablet.

Storage

  • Store at room temperature between 68°F and 77°F (20°C and 25°C). You may briefly store the drug at temperatures as low as 59°F (15°C) and as high as 86°F (30°C).
  • Keep this drug away from light.
  • Don’t store this medication in moist or damp areas, such as bathrooms.

Refills

A prescription for this medication is not refillable. You or your pharmacy will have to contact your doctor for a new prescription if you need this medication refilled.

There are other drugs available to treat your condition. Some may be better suited for you than others. Talk to your doctor about other drug options that may work for you.

Disclaimer: Healthline has made every effort to make certain that all information is factually correct, comprehensive, and up-to-date. However, this article should not be used as a substitute for the knowledge and expertise of a licensed healthcare professional. You should always consult your doctor or other healthcare professional before taking any medication. The drug information contained herein is subject to change and is not intended to cover all possible uses, directions, precautions, warnings, drug interactions, allergic reactions, or adverse effects. The absence of warnings or other information for a given drug does not indicate that the drug or drug combination is safe, effective, or appropriate for all patients or all specific uses.