Beta-blockers are a class of medication used to block the effects of stress hormones such as adrenaline on the heart. They’re often prescribed for irregular heartbeat, high blood pressure, and after heart attacks.

Less commonly, beta-blockers may be used to treat:

Doctors typically turn to beta-blockers for high blood pressure when other medications, such as diuretics, aren’t working or have too many side effects.

Beta-blockers may be used with other blood pressure-lowering medications, including ACE inhibitors and calcium channel blockers.

Beta-blockers have been shown to have some health benefits outside of helping the heart. For example, they protect bones by preventing the kidneys from excreting calcium into urine, and block stress hormones that could otherwise cause bone thinning over time.

Because of the way they work in the body, beta-blockers are also called beta-adrenergic blocking substances.

Different types of beta-blockers work differently. In general, these medications enhance the heart’s ability to relax. Your heart will beat slower and less forcefully when beta-blockers are working. This can help reduce blood pressure and alleviate irregular heart rhythms.

Some beta-blockers work only on the heart itself, while others affect the heart and blood vessels.

Your doctor may prescribe beta-blockers even if you have few symptoms of heart problems or heart failure. These medications can actually improve the heart’s ability to beat.

Commonly prescribed beta-blockers include:

Beta-blockers are available in different formulas with different routes of administration, including oral, intravenous, and ophthalmic.

Beta-blockers are usually taken once or twice a day with meals, and should generally be taken at the same time every day.

Always take your medication as prescribed. Let your doctor know if you’re having side effects. You should not stop taking your beta-blocker without consulting with your doctor first.

Beta-blockers are used to reduce the speed of your heartbeat and lower your blood pressure. They do so by preventing the hormone adrenaline, as well as other stress hormones, from binding to beta receptors throughout your body.

Beta-blockers are Food and Drug Administration (FDA) approved for the treatment of heart- and blood pressure-related conditions, including:

  • tachycardia
  • high blood pressure (hypertension)
  • heart attack (myocardial infarction)
  • congestive heart failure
  • cardiac arrhythmias
  • coronary artery disease
  • overactive thyroid (hyperthyroidism)
  • essential tremor
  • aortic dissection
  • portal hypertension

Beta-blockers are sometimes prescribed by doctors for off-label use to treat other conditions, including:

Side effects of these medications can vary. Many people will experience:

  • fatigue
  • cold hands
  • headache
  • digestive problems
  • constipation
  • diarrhea
  • dizziness

Rarely, you may experience:

  • shortness of breath
  • trouble sleeping
  • decreased libido
  • depression

If you accidentally take a larger dose than recommended, you may experience:

If you know that an overdose has occurred, call your doctor or local poison control center. The U.S. National Poison Control Center phone number is 800-222-1222.

Some older beta-blockers — such as atenolol and metoprolol — have been reported to cause weight gain. Fluid retention and accompanying weight gain can be signs of have heart failure, or that heart failure is getting worse.

Be sure to let your doctor know if you gain more than 2 to 3 pounds within a day, gain more than 5 pounds within a week, or your symptoms worsen.

You may also notice some changes in the way your heart works during day-to-day life. For example, beta-blockers prevent spikes in heart rate. You may notice that your heart rate doesn’t climb as high as it normally would during exercise.

Speak with your doctor if you’re concerned about your workouts while taking this medication. They may recommend a stress test to determine your target heart rate during cardio.

Stress tests can also help your doctor determine how hard you feel you’re working during a workout. This is known as the rate of perceived exertion.

Other medications can increase or decrease the effect of beta-blockers, so be sure to tell your doctor about all medications, vitamins, and herbal supplements you may be taking.

Beta-blockers can interact with medications such as:

  • ACE inhibitors
  • allergy medications such as ephedrine, noradrenaline, or adrenaline
  • alpha-blockers
  • anesthetics
  • anti-arrhythmics
  • anti-ulcer medications
  • antidepressants
  • antihypertensive and antianginal drugs
  • asthma drugs
  • calcium channel blockers
  • digitalis glycosides
  • HMG-CoA reductase inhibitors
  • inotropic agents
  • isoproterenol and dobutamine
  • neuroleptic drugs
  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • oral hypoglycemics
  • other blood pressure medications
  • psychotropic drugs
  • reserpine
  • rifampicin (also known as rifampin)
  • thyroxine
  • warfarin

Beta-blockers should not be used by people with:

  • a history of fluid retention without diuretic use
  • severe heart failure
  • Raynaud’s disease

Historically, beta-blockers have been contraindicated in people with asthma, but this group can safely use cardio-selective beta-blockers, also known as beta-1 selective.

Because beta-blockers may affect blood sugar management, they’re not usually recommended for people with diabetes.

Tell your doctor if you are pregnant, plan to become pregnant, or are breastfeeding while taking beta-blockers.

If you’re having surgery, including dental surgery while taking beta-blockers, tell your doctor or dentist.

Do not stop taking a beta-blocker without consulting with your doctor. Stopping beta-blockers suddenly could cause health complications, including:

  • heart palpitations
  • raised blood pressure
  • chest pain (angina)

Beta-blockers are a commonly prescribed medication used to lower blood pressure, protect against heart attacks, and treat various heart-related conditions. They’re also prescribed off-label for glaucoma, migraine, and anxiety.

Beta-blockers lower your blood pressure by blocking the effects of stress hormones on your heart. Follow the directions on your prescription when taking beta-blockers.

Be sure to tell your doctor about any other drugs, herbs, or supplements you’re taking, as these could affect how beta-blockers work.