Your heart rate fluctuates throughout the day; this is normal. Acceleration occurs during exercise, deceleration during post-exercise recovery, and the lowest rate typically happens during sleep.

Individuals may occasionally experience a heart rate that is noticeably lower than average. This slow heart rate is termed bradycardia; it usually isn’t a cause for concern. And it may result from various factors, including medications, fitness level, conduction system, heart infections, and sleep apnea. But, of course, a heart rate of 60 beats or less per minute is considered clinically significant.

However, a sluggish heart rate may also indicate an underlying health issue, such as cardiac dysfunction. Suppose you experience a slow heart rate at rest and other symptoms of bradycardia, such as dizziness, then you must immediately seek for medical help.

Understanding a slow heart rate (Bradycardia)

At rest, a healthy human heart beats anywhere from 60 to 100 beats per minute (bpm), as stated by the American Heart Association (AHA). However, there are situations when your heart rate may be higher or slower than the recommended rate.

Bradycardia is when the heart beats at 60 beats or less per minute or less frequently.

When determining how slow is too slow, factors such as age and health should be considered. For instance, the elderly are at a higher risk for bradycardia.

In adults, bradycardia is considered to exist when the resting heart rate is less than 60 BPM. Nonetheless, there are a few notable cases. During a profound sleep, your heart rate can drop below 60 beats per minute. At rest, the heart rates of fit and active adults are often lower than 60 beats per minute.

Also, bradycardia can occur in physically active people without any negative consequences. But, a sluggish heart rate may indicate severe complications like heart failure or cardiac arrest.

So, how can you know you have bradycardia?

Symptoms of bradycardia

An abnormally slow heart rate can reduce blood flow to your heart and brain, leading to a lack of oxygen and perhaps these symptoms:

  • Fatigue
  • Chest pain or pressure in the chest
  • Disorientation or memory loss
  • Feeling faint or dizzy
  • Shortness of breath
  • Abdominal discomfort

A variety of factors may cause bradycardia symptoms. Therefore, get a proper diagnosis and treatment, especially if you are worried that your heart rate is too low.

What causes a slow heart rate?

A slow heart rate may be a result of several factors, including:

  • Conduction system disorders
  • Obstructive sleep apnea
  • Medications
  • Heart infection
  • Heart attack
  • Hypothyroidism
  • Oxygen deprivation

Let’s find out how these elements slow your heart rate:

Oxygen deprivation

Hypoxia is the medical word for lack of oxygen reaching the body’s cells and tissues. An individual may experience hypoxia in the event of a life-threatening situation like choking or an extreme asthma attack.

Image alt text: slow heart rate; a heart rate and arterial pressure waves.

Author credit: By John Campbell –, CC0,

Hypoxia can also be brought on by long-term health issues such as chronic obstructive lung disease, which may slow your heart rate. If hypoxia is the reason for a slowed heart rate, then the patient must immediately seek treatment.

Certain medications

Certain medications, especially heart treatment drugs, may slow or raise your heart rate. For instance, heart disease and hypertension drugs are among those that can slow the heart. Doctors give beta-blockers and calcium channel blockers to treat high heart rates and heart disorders, which may help reduce the heart rate.

Drugs prescribed to treat heart conditions may produce symptoms like:

  • Lightheadedness
  • Slow heart rate
  • Flushing and sweating
  • Breathing difficulties

Those who take a new drug and have symptoms of bradycardia should see a physician immediately.

Pain relievers, sedatives, psychiatric drugs, and hepatitis C drugs are some of the others that can affect your heart rate.

It’s possible that the drugs’ effects on the heart rate will be too profound in some people. Therefore, tell your doctor if you’ve recently started a new medicine and have experienced any of the aforementioned symptoms, including a slowed heart rate. Your heart rate may need to be monitored, or they may recommend a different treatment option.

Heart-damaging illness

When various medical issues damage the heart, it might begin to pump less efficiently and gradually slow down. A few heart-harming conditions are:

Heart infections like endocarditis and myocarditis: These are forms of cardiac inflammation. Endocarditis is the inflammation or swelling of the heart’s endocardium or inner lining. At the same time, myocarditis is the swelling or inflammation of the heart muscles.

These conditions can disrupt your heart’s electrical wiring running around the heart’s lining, thus reducing your heart rhythm. Both illnesses have their roots in infections that extend to the core. Rarely can they develop due to a viral, parasitic, bacterial, or fungal infection.

However, you may also get myocarditis when exposed to radiation, medications used in cancer treatment, or inflammatory disorders. After the underlying cause of endocarditis or myocarditis has been treated, the patient’s heart rate typically returns to normal; nevertheless, a pacemaker might be essential to keep the patient’s heart rate from fluctuating.


Hypothyroidism, often known as “underactive thyroid,” occurs when your thyroid gland fails to generate enough hormones. Your metabolism is just one of the many bodily processes that these hormones regulate. Thyroidism reduces metabolism, which in turn slows the heart rate.

Those with this condition may experience symptoms like:

  • Sluggish heart rate
  • Fatigue and depression
  • Weight gain

The condition is brought on by various elements, including an autoimmune disorder, thyroid-related surgery or radiotherapy, certain drugs, pregnancy, or insufficient or excessive dietary iodine intake.

Hypothyroidism tends to occur in middle-aged women, especially those with thyroid problems. And it can progress to a life-threatening condition characterized by severely reduced blood pressure, shallow core temperature, and potentially coma if not treated in time.

Obstructive Sleep Apnea

This condition is characterized by breathing difficulties during sleeping, making it difficult for sufferers to take in enough oxygen. As a result, you may find yourself pausing to breathe rather often. People’s sleep quality diminishes, even if they are unaware of it.

Your heart rate may drop much lower than normal during sleep during these intervals or pauses. This, combined with frequent awakenings, might cause a person to feel excessively sleepy during the day.

Excessive oral soft tissue is the leading cause of obstructive sleep apnea. Those who are overweight are more likely to develop the illness, and men are more likely to be affected overall. Therefore, you should strive for normal-weight obesity to reduce your risk of cardiometabolic complications.

With sleep apnea, you may experience symptoms like:

  • Reduced heart rate
  • Nighttime snoring
  • Lightheadedness
  • Overwhelming sleepiness during the day

Ensure you immediately see your healthcare provider when you experience any of these symptoms. Besides, untreated sleep apnea may result in severe complications like irregular cardiac rhythms and high blood pressure.

Heart Attacks

Heart attacks occur when the blood supply to the heart is cut off, primarily because of a blockage in a large coronary artery.

During a heart attack, the oxygen-rich blood that normally flows to your heart’s electrical system is cut off in roughly 15–25% of cases. And when the oxygen supply to the heart is inadequate, the cardiac rhythm slows.

If you think you could be experiencing a heart attack, dial 911 or head to the nearest emergency room immediately. The extent of your heart attack should determine the course of treatment. Medication, stents-tiny mesh tubes used to prop open clogged arteries, and surgery are all potential components.

Conduction system disorders

Once the heart’s electrical system becomes dysfunctional, the result is heart disease. The “wiring” in your body that regulates your pulse may become frayed as time passes. If this happens, the signal that tells your heart to continue beating will weaken, slow down, or stop altogether in extreme situations.

When to Seek Medical Attention

If your heart rate is slow, it’s essential to monitor it. Still, paying attention to any other symptoms you might be experiencing is also necessary. This is because a sluggish heart rate might not be a cause for concern if you are generally healthy. The following symptoms warrant a visit to the doctor:

  • Tingling in the chest
  • The inability to stand or relax without feeling faint or lightheaded.
  • Symptoms include fatigue and inability to perform daily tasks

Also, visit the emergency room if you experience any of these symptoms:

  • Confusion
  • Chills and fever
  • Shortness of breath
  • Disorientation or loss of awareness (unconsciousness)

Variable Heart Rate Treatment Alternatives

A sluggish heart rate may not necessarily require medical intervention. If, however, a slow heart rate is the cause of life-threatening symptoms, then therapy is warranted.

However, treatment for slow heart rate is condition-specific and depends on what is causing it. Some tests can help a doctor determine what’s causing a patient’s bradycardia. They may perform physical, imaging, and blood tests.

  • Modifying current heart medication
  • Checking one’s pulse or blood pressure regularly
  • Pharmacological treatment for metabolic conditions such as hypothyroidism
  • Adopting a new way of life by reducing fat intake, increasing physical activity, and giving up smoking


Since heart illness is so potentially lethal, people must pay close attention to any changes in their heart rate, blood pressure, or other vital signs. Yet, it’s not always serious if your heart rate is low. Occasionally, a bradycardia reading can indicate general health and wellness. Therefore, check with your doctor whenever you have irregular cardiac rhythms.