Merck Manual

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Andrea D. Thompson

, MD, PhD, University of Michigan;

Michael J. Shea

, MD, Michigan Medicine at the University of Michigan

Reviewed/Revised Aug 2022 | Modified Sep 2022
Topic Resources

Palpitations are common. Some people find them unpleasant and alarming, but they rarely indicate a life-threatening heart disorder. Many people without heart disease also have palpitations.

Causes of Palpitations

Ordinarily, people do not notice the beating of their heart. However, many people can feel their heart beating when something causes it to beat more forcefully or rapidly than usual. Such rapid, forceful beats are usually a normal response by the heart (sinus tachycardia). Causes include the following:

In other cases, palpitations result from a disturbance of heart rhythm (arrhythmia).

Types of arrhythmias

The most common arrhythmias include

Both of these arrhythmias usually occur in people without a heart disorder and are harmless. The premature beat itself is not felt. What is felt is the following normal heartbeat, which occurs after a slight delay and is slightly stronger than usual. Although people feel as if their heart skipped a beat, it actually did not.

Other arrhythmias that cause palpitations and may be caused by serious heart disorders include

These other arrhythmias involve the heart beating much faster than normal. Arrhythmias in which the heart beats too slowly rarely cause palpitations, although some people do feel the slow rate.

Causes of arrhythmias

Some arrhythmias (for example, atrial premature beats, ventricular premature beats, or PSVT) often occur in people who have no serious underlying disorders. Others are often caused by a serious heart disorder or a disorder elsewhere in the body.

Disorders not related to the heart that may cause arrhythmias include


Arrhythmias that cause the heart to beat too fast can cause complications (particularly in older people). If the heart goes too fast, it may not be able to pump blood adequately, and people may feel faint or pass out or develop heart failure Heart Failure (HF) Heart failure is a disorder in which the heart is unable to keep up with the demands of the body, leading to reduced blood flow, back-up (congestion) of blood in the veins and lungs, and/or... read more Heart Failure (HF) . Heart failure occurs mainly in people who have previously had heart failure or a heart attack, although it can occur in other people if the heart rate is very fast or if the heart beats too fast for a long time. A rapid heart rate also increases the oxygen needs of the heart muscle. People who have narrowing of the arteries to the heart muscle (coronary artery disease Overview of Coronary Artery Disease (CAD) Coronary artery disease is a condition in which the blood supply to the heart muscle is partially or completely blocked. The heart muscle needs a constant supply of oxygen-rich blood. The coronary... read more Overview of Coronary Artery Disease (CAD) ) can develop chest pain due to angina or a heart attack (which may be fatal).

Some arrhythmias, particularly ventricular tachycardia, are unstable and can lead directly to cardiac arrest.

Evaluation of Palpitations

Although not all palpitations are caused by a heart disorder, the consequences of some heart disorders are so serious that people with palpitations should usually be evaluated by a doctor. The following information can help people decide when to see a doctor and help them know what to expect during the evaluation.

Warning signs

In people with palpitations, certain symptoms and characteristics are cause for concern. They include

  • Light-headedness or fainting

  • Chest pain or pressure

  • Shortness of breath

  • Pulse rate over 120 per minute or less than 45 per minute

  • Having heart disease or a family history of sudden death, recurrent fainting, or unexplained seizure disorder

  • Symptoms occur during exercise, particularly if they cause loss of consciousness

When to see a doctor

People who have palpitations and any warning signs should go to an emergency department right away, as should those who have continuous, ongoing palpitations. Those who have fainting, chest pain, or shortness of breath should call emergency services.

People without warning signs who have occasional palpitations or had an episode that stopped should call their doctor. The doctor will determine how quickly they need to be seen based on their age, underlying conditions, and other symptoms.

What the doctor does

Doctors first ask questions about the person's symptoms and medical history. Doctors then do a physical examination. What they find during the history and physical examination helps determine the possible cause.

Doctors ask

  • How often palpitations occur

  • How long palpitations last

  • What factors (for example, emotional distress, activity, or intake of caffeine or other drugs) trigger or worsen palpitations

  • What drugs, including caffeine, the person is taking

Sometimes doctors ask the person to tap out the rate and cadence of palpitations because the pattern of beats can help them determine the cause.

The physical examination begins with the doctor checking the vital signs (pulse, temperature, and blood pressure). The pulse rate and whether the pulse is regular or irregular help suggest causes. An elevated temperature suggests fever is the cause. A low blood pressure does not suggest a cause but indicates extreme urgency.

Doctors listen to the heart for abnormal sounds that might indicate a valve disorder or heart inflammation. They listen to the lungs for sounds that indicate heart failure. They look at and feel the front of the neck to see if the thyroid gland is enlarged or inflamed.

Palpitations that occur with other symptoms, such as shortness of breath, chest pain, weakness, fatigue, or fainting, are more likely to result from an abnormal heart rhythm or a serious disorder.



Even though most causes of palpitations are not serious, testing typically is done.

  • Electrocardiography (ECG), sometimes with ambulatory monitoring

  • Laboratory testing

  • Sometimes imaging studies, stress testing, or both

  • Sometimes electrophysiologic testing

ECG Electrocardiography Electrocardiography (ECG) is a quick, simple, painless medical test that measures the heart’s electrical impulses. During an ECG, the heart's electrical impulses are measured, amplified, and... read more Electrocardiography is done. If the ECG is done while the person is having palpitations or an abnormal pulse rate, the diagnosis is usually clear. However, only a few of the possible causes produce an abnormal ECG when people are not having palpitations. Thus, people who have intermittent palpitations may need to wear an ECG monitor for a day or two (Holter monitoring—see figure ) or for a longer period (event recorder) to detect brief or irregularly occurring abnormal rhythms. In some people, doctors may insert a device underneath the skin to monitor the heart beat. This device is called a loop recorder, and it continuously monitors the person's heartbeat. Doctors can then use an external monitor to check the loop recorder for abnormal heart rhythms. Some commercially available products such as fitness trackers, which monitor heart rate, and other trackers that monitor track heart rhythms, are available for smart phones and watches but provide more limited information.

Laboratory testing is needed. Doctors do a complete blood count and measure serum electrolytes, including potassium, magnesium, and calcium. Doctors may measure other substances in the blood (cardiac markers) if the person has other symptoms that suggest a possible acute coronary syndrome Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) Acute coronary syndromes result from a sudden blockage in a coronary artery. This blockage causes unstable angina or a heart attack (myocardial infarction), depending on the location and amount... read more Acute Coronary Syndromes (Heart Attack; Myocardial Infarction; Unstable Angina) . Doctors measure levels of thyroid hormone in the blood if they suspect an overactive thyroid and measure levels of other hormones in people who may have pheochromocytoma Pheochromocytoma A pheochromocytoma is a tumor that usually originates from the chromaffin cells of the adrenal glands, causing overproduction of catecholamines, powerful hormones that induce high blood pressure... read more . Other tests may be done, depending on what other causes doctors suspect.

Electrophysiologic (EP) testing Electrophysiologic Testing Electrophysiologic testing measures the heart's electrical activity through wire electrodes inserted into all 4 heart chambers. Electrophysiologic testing is used to evaluate serious abnormalities... read more is done when people's symptoms are severe and doctors suspect a dangerous heart rhythm problem that was not found with other tests. In this test, doctors pass small electrodes through a vein into the heart. The electrodes record the heart's electrical activity in more detail than an ECG does.

Treatment of Palpitations

Drugs and substances such as caffeine that are known to worsen a person's palpitations are stopped. If dangerous or debilitating arrhythmias are caused by a necessary therapeutic drug, doctors try a different drug.

Doctors usually simply provide reassurance for people with atrial premature beats or ventricular premature beats that are not caused by a heart disorder. If such harmless palpitations are very bothersome, doctors sometimes give a beta-blocker (a type of antiarrhythmic drug). Other identified rhythm disturbances and underlying disorders Abnormal Heart Rhythms are investigated and treated. Doctors often first give rhythm-controlling drugs (such as digoxin, flecainide, verapamil, diltiazem, or amiodarone). However, many of these drugs can themselves cause rhythm disturbances as well as other side effects.

For certain arrhythmias (for example, atrial flutter, PSVT, and atrioventricular nodal reentrant tachycardia), radiofrequency ablation Destroying Abnormal Heart Tissue (Ablation) There are many causes of abnormal heart rhythms (arrhythmias). Some arrhythmias are harmless and do not need treatment. Sometimes arrhythmias stop on their own or with changes in lifestyle,... read more , a more invasive treatment, is often the best option. In addition, if drugs are not effective or if people have certain dangerous rhythm disturbances, doctors may use invasive treatments such as direct current cardioversion or implantation of a combination pacemaker and defibrillator. The choice of procedure depends on the specific condition causing the disturbance.

Essentials for Older People

Older people are at particular risk of side effects due to antiarrhythmic drugs. Older people are likely to have several health problems and take several drugs, and these drug combinations may put them at risk of side effects. In older people, the kidneys are less effective at filtering drugs from the blood, which contributes to the risk of side effects. Some older people may even need a pacemaker before they can take antiarrhythmic drugs.

Key Points

  • Palpitations are common, and they have many causes that range from harmless to life-threatening.

  • People who have other symptoms such as light-headedness, chest pain or pressure, or shortness of breath may have a serious problem and should see a doctor quickly.

  • ECG, certain blood tests, and often other specialized cardiac tests are done.

  • Treatment depends on the cause.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Cafcit, NoDoz, Stay Awake, Vivarin
Digitek , Lanoxicaps, Lanoxin, Lanoxin Pediatric
Commit, Habitrol, Nicoderm CQ, NICOrelief , Nicorette, Nicotrol, Nicotrol NS
Accuneb, ProAir digihaler, Proair HFA, ProAir RespiClick, Proventil, Proventil HFA, Proventil Repetabs, Respirol , Ventolin, Ventolin HFA, Ventolin Syrup, Volmax, VoSpire ER
Adrenaclick, Adrenalin, Auvi-Q, Epifrin, EpiPen, Epipen Jr , Primatene Mist, SYMJEPI, Twinject
Elixophyllin, Quibron T, Quibron T/SR, Respbid, Slo-Bid, Slo-Phyllin, Theo X, Theo-24, Theo-Bid Duracap, TheoCap, Theochron, Theo-Dur, Theo-Dur Sprinkle , Theolair, Theolair SR, Theovent LA, T-Phyl, Uni-Dur, Uniphyl
Calan, Calan SR, Covera-HS, Isoptin, Isoptin SR, Verelan, Verelan PM
Cardizem, Cardizem CD, Cardizem LA, Cardizem SR, Cartia XT , Dilacor XR, Dilt-CD , Diltia XT, Diltzac, Matzim LA, Taztia XT, TIADYLT ER, Tiamate, Tiazac
Cordarone, Nexterone, Pacerone
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