What is an acceptable heart rate on beta blockers?

In this article:

• How beta blockers change your heart rate
• “Normal” heart rate
• Normal heart rate on beta blockers
• Red flags
• Monitoring your heart rate
• Living with beta blockers

In this article

• How beta blockers change your heart rate
• “Normal” heart rate
• Normal heart rate on beta blockers
• Red flags
• Monitoring your heart rate
• Living with beta blockers

Beta blockers are among the most commonly prescribed medications for people with heart conditions like high blood pressure (hypertension), heart rhythm disorders (arrhythmias or tachycardia), and heart failure. In fact, roughly 10% of Americans take a beta blocker such as metoprolol, carvedilol, or atenolol. They work by preventing the absorption of certain chemicals in your brain, which relaxes blood vessels to allow the heart to pump more easily. The two main effects are decreased heart rate and blood pressure.

However, what’s considered an acceptable or healthy heart rate for someone taking beta blockers varies based on why the beta blockers were prescribed in the first place. Read on to find out what to expect and when you should call your provider or cardiologist.

How beta blockers change your heart rate

“Beta blockers (specifically cardioselective beta1 blockers) reduce the effects of the stress hormones adrenaline (epinephrine) and noradrenaline (norepinephrine) on the heart,” explains pharmacologist Nilank Shah, MD, an associate professor of physiology at Touro College of Osteopathic Medicine. “As a result, the heart beats more slowly, pumps with less force, and responds less dramatically to physical or emotional stress.”

Depending on the individual, this change can manifest in different ways. Some people never notice a difference, while others could experience dramatic symptoms. “I usually review the signs of slow heart rate with patients prior to starting a beta blocker,” says Lu Chen, MD, a cardiac electrophysiologist at MemorialCare Heart & Vascular Institute at Orange Coast Medical Center in Fountain Valley, California. “The most severe form would be black out episodes, or syncope.” But before that, there are other, more subtle signs of a too-slow heart rate, also known as bradycardia. Per Drs. Shah and Chen, these include:

• Dizziness
• Increased tiredness
• Reduced tolerance for exercise
• Depression
• Cold hands or feet
• Feeling slower than usual
• No racing heart during stress or exercise

These symptoms could indicate a need for a dose adjustment to prevent your heart rate from being below or slower than the acceptable range.

What’s a “normal” heart rate without beta blockers?

A normal resting heart rate for most healthy adults is between 60 and 100 beats per minute (bpm), according to the American Heart Association. However, certain factors can change your resting heart rate. For example, athletes and people who exercise regularly tend to have lower resting heart rates (some as low as 40 beats per minute). Typically, lower resting heart rates are a sign of good cardiac health, a signal that your heart is in just as good shape as your muscles. 

The biggest concern with resting heart rate is that it becomes chronically high. Dehydration, fever, caffeine, and stress can cause temporary increases in heart rate, while certain medications and conditions like anemia or an overactive thyroid (naturally hyperthyroid or excessive thyroid medication) can raise your resting heart rate and keep it elevated. 

What’s a normal heart rate on beta blockers?

“There is no single normal heart rate for everyone on beta blockers,” Dr. Shah says. “Rather than focusing on a specific number, clinicians consider how the person feels, their overall heart function, blood pressure, and the reason the medication was prescribed.” That last factor plays perhaps the biggest role in what to expect with your heart rate on beta blockers. 

“We target different heart rates for different conditions,” Dr. Chen says. 

When to be concerned and what to do

While serious complications are uncommon, they may occur from taking beta blockers, Dr. Shah says. They may include:

Excessively slow heart rate

“Beta blockers can certainly slow down the heart rate and significantly slow down the communications between the upper and lower chambers of the heart,” Dr. Chen explains. If this is the case, he adds that it will most likely present as black out episodes, persistent dizziness or lightheadedness, or extreme fatigue.

Inability to raise heart rate

Chronotropic incompetence is the technical term for the inability to increase your heart rate during physical activity or stress, which is a common side effect of beta blockers. Beta blockers can also make it more difficult to increase your heart rate during exercise, “an effect that is often expected and intentional,” Dr. Shah says. Typically, you calculate your maximum heart rate when working out by subtracting your age from 220. 

Because beta blockers limit the amount your heart rate increases, you may not be able to rely on your heart rate to check your effort or exertion during a workout. Instead, use a perceived exertion scale, noting how hard you’re breathing or how much effort you’re exerting to determine whether you’re reaching your goal intensity. 

Chronotropic incompetence can become a concern, Dr. Shah notes, when it translates to “a reduced ability of the heart to speed up during illness or emergencies.” This could mean that your heart isn’t able to pump blood through the body and to the brain quickly enough in a medical emergency, which can lead to potentially dire outcomes.

Rebound fast heart rate

Dr. Shah says that if you were to stop taking beta blockers suddenly, you may experience a rebound effect, like a dangerously fast heart rate or high blood pressure. Symptoms of a high heart rate include palpitations, chest pain, and shortness of breath. A too-high heart rate can cause lightheadedness and fainting, just as a too-low heart rate can.

When to seek medical attention

Contact a healthcare professional immediately or call 911 if you experience any of the following serious symptoms:

• Fainting or blacking out
• Persistent dizziness or lightheadedness
• Shortness of breath at rest
• Chest pain
• Heart palpitations
• Extreme fatigue

“Emergency care is needed for collapse, severe chest pain, or difficulty breathing,” Dr. Shah adds. These could be signs of a heart attack or worsening heart disease.

Monitoring your heart rate

Compulsively checking your heart rate while on beta blockers can sometimes do more harm than good, creating unnecessary stress. That’s why Dr. Chen says that keeping an eye out for symptoms like those above can be the best way to recognize that your heart rate has dropped too low without ever checking your pulse. Still, if you have a device that can check your heart rate, such as a blood pressure monitor, wearable health tracker, or smartwatch, it can be helpful to take readings occasionally, especially if you aren’t feeling like yourself.

The American Heart Association notes that if you’re starting to take beta blockers, your healthcare provider may ask you to monitor and log your blood pressure and heart rate at set intervals to help you determine if you’re on the right medication at the right dose. Most providers suggest checking once a day, at different times of day. Patients should check their blood pressure and pulse anytime they feel symptomatic with dizziness, weakness, or chest pain. 

Living with beta blockers

“For patients with heart conditions that require beta blockers, the specific recommendations are individually based,” Dr. Chen says. However, they often include many of the same lifestyle strategies that people who are not taking beta blockers may aim to incorporate into their daily lives to improve their heart health. Dr. Chen recommends the following strategies:

• Eating a balanced diet, like the Mediterranean diet, which has been shown to be beneficial for cardiovascular health
• Getting 150 minutes of moderate- to high-intensity exercise (as tolerated) per week
• Limiting alcohol intake to less than 2 alcoholic drinks/day for men or less than 1 alcoholic drink/day for women
• Avoiding all nicotine products

For many people, beta blockers are a life-changing medication. However, like with any medication, each individual reacts differently. It is important to work closely with your healthcare provider to make sure you are on the right dose and the right beta blocker, which means monitoring and reporting any side effects you experience—especially those that could be caused by changes in your heart rate.