Beta-blockers are often prescribed for irregular heartbeats (arrhythmias), high blood pressure, and after heart attacks. They’re a class of medication used to block the effects of stress hormones like adrenaline (also called epinephrine) on the heart.
Less commonly, beta-blockers may be used to treat:
- anxiety disorders
Doctors typically turn to beta-blockers for high blood pressure when other medications like diuretics aren't working or have too many side effects. They may be used in combination with other blood pressure lowering medications such as ACE inhibitors or calcium channel blockers.
How They Work
Beta-blockers are also called beta-adrenergic blocking substances due to the way they work in the body.
Different types of beta-blockers work differently, but 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 to reduce blood pressure and alleviate irregular heart rhythms. Some beta-blockers only work on the heart itself, while others impact 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 have been shown to have some positive health effects outside of helping the heart. For example, they protect bones by preventing the kidneys from excreting calcium into urine. These drugs block stress hormones that could otherwise cause thinning over time.
Beta-blockers aren’t a first line of treatment for thinning bones or osteoporosis. Stronger bones just may be an extra benefit of taking these medications.
Side Effects and Risks
People with asthma typically shouldn’t take beta-blockers since they can trigger asthma attacks. Because beta-blockers may affect the control of blood sugar, they’re usually not recommended for people with diabetes.
Side effects of these medications can vary. Many people will experience:
- cold hands
- digestive problems
Rarely, you may experience:
- shortness of breath
- trouble sleeping
- decreased libido
If you accidentally take a larger dose than recommended, you may experience:
- difficulty breathing
- changes in vision
- irregular heartbeats
If you know that an overdose has occurred, call your doctor or local poison control center.
Some of the older beta-blockers — like atenolol and metaprolol — have been reported to cause an average weight gain of 4 pounds. Fluid retention and accompanying weight gain can be signs of heart failure or worsening heart failure. Be sure to let your doctor know if you gain more than 3 to 4 pounds or if your symptoms worsen.
You also may 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 and how hard you feel you’re working during a workout (rate of perceived exertion).
Taking Your Medication
Beta-blockers are often taken with meals, though they’ll come with special instructions. Take your medication as prescribed. Consult your doctor if you’re having side effects and don’t stop taking the medication without your doctor’s consent.