Generic name: metoprolol [ me-TOE-pro-lol ]
Brand names: Kapspargo Sprinkle, Lopressor, Metoprolol Succinate ER, Metoprolol Tartrate, Toprol-XL
Drug class: Cardioselective beta blockers

What is Lopressor?

Lopressor is a beta-blocker that affects the heart and circulation (blood flow through arteries and veins).

Lopressor is used to treat angina (chest pain) and hypertension (high blood pressure). It is also used to lower your risk of death or needing to be hospitalized for heart failure.

Lopressor may also be used for other purposes not listed in this medication guide.

Important Information

You should not use Lopressor if you have a serious heart problem (heart block, sick sinus syndrome, slow heart rate), severe circulation problems, severe heart failure, or a history of slow heart beats that caused fainting.

Before taking this medicine

You should not use this medicine if you are allergic to Lopressor, or other beta-blockers (atenolol, carvedilol, labetalol, nadolol, nebivolol, propranolol, sotalol, and others), or if you have:

• a serious heart problem such as heart block, sick sinus syndrome, or slow heart rate;

• severe circulation problems;

• severe heart failure (that required you to be in the hospital); or

• a history of slow heart beats that have caused you to faint.

Tell your doctor if you have ever had:

• asthma, chronic obstructive pulmonary disease (COPD), sleep apnea, or other breathing disorder;

• diabetes (taking Lopressor may make it harder for you to tell when you have low blood sugar);

• liver disease;

• congestive heart failure;

• problems with circulation (such as Raynaud's syndrome);

• a thyroid disorder; or

• pheochromocytoma (tumor of the adrenal gland).

Do not give this medicine to a child without medical advice.

Tell your doctor if you are pregnant or plan to become pregnant. It is not known whether Lopressor will harm an unborn baby. However, having high blood pressure during pregnancy may cause complications such as diabetes or eclampsia (dangerously high blood pressure that can lead to medical problems in both mother and baby). The benefit of treating hypertension may outweigh any risks to the baby.

Ask a doctor before using this medicine if you are breast-feeding. Metoprolol can pass into breast milk and may cause dry skin, dry mouth, diarrhea, constipation, or slow heartbeats in your baby.

How should I take Lopressor?

Follow all directions on your prescription label and read all medication guides or instruction sheets. Your doctor may occasionally change your dose. Use the medicine exactly as directed.

Lopressor should be taken with a meal or just after a meal.

Take the medicine at the same time each day.

Swallow the capsule whole and do not crush, chew, break, or open it.

A Toprol XL tablet can be divided in half if your doctor has told you to do so. Swallow the half-tablet whole, without chewing or crushing.

Measure liquid medicine carefully. Use the dosing syringe provided, or use a medicine dose-measuring device (not a kitchen spoon).

You will need frequent medical tests, and your blood pressure will need to be checked often.

If you need surgery, tell the surgeon ahead of time that you are using Lopressor.

You should not stop using Lopressor suddenly. Stopping suddenly may make your condition worse.

If you have high blood pressure, keep using Lopressor even if you feel well. High blood pressure often has no symptoms. You may need to use Lopressor for the rest of your life.

Store at room temperature away from moisture and heat.

What happens if I miss a dose?

Skip the missed dose and use your next dose at the regular time. Do not use two doses at one time.

What happens if I overdose?

Seek emergency medical attention or call the Poison Help line at 1-800-222-1222.

What should I avoid while taking Lopressor?

Avoid driving or hazardous activity until you know how Lopressor will affect you. Your reactions could be impaired.

Drinking alcohol can increase certain side effects of metoprolol.

Lopressor side effects

Get emergency medical help if you have signs of an allergic reaction: hives; difficulty breathing; swelling of your face, lips, tongue, or throat.

Call your doctor at once if you have:

• very slow heartbeats;

• a light-headed feeling, like you might pass out;

• shortness of breath (even with mild exertion), swelling, rapid weight gain; or

• cold feeling in your hands and feet.

Common side effects may include:

• dizziness, tired feeling;

• depression, confusion, memory problems;

• nightmares, trouble sleeping;

• diarrhea; or

• mild itching or rash.

This is not a complete list of side effects and others may occur. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Related/similar drugs

What other drugs will affect Lopressor?

Tell your doctor about all your current medicines. Many drugs can affect Lopressor, especially:

• any other heart or blood pressure medications;

• epinephrine (Epi-Pen);

• an antidepressant;

• an ergot medicine--dihydroergotamine, ergonovine, ergotamine, methylergonovine; or

• an MAO inhibitor--isocarboxazid, linezolid, phenelzine, rasagiline, selegiline, tranylcypromine.

This list is not complete and many other drugs may affect Lopressor. This includes prescription and over-the-counter medicines, vitamins, and herbal products. Not all possible drug interactions are listed here.

Popular FAQ

Further information

Remember, keep this and all other medicines out of the reach of children, never share your medicines with others, and use this medication only for the indication prescribed.

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Medical Disclaimer

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