Causes of Heart Palpitations: Why Does My Heart Race, Pound, Flutter or Skip?
Heart palpitations are the sensation of being unusually aware of your heartbeat. They may feel like racing, pounding, fluttering, skipped beats, extra beats or an irregular rhythm.
Sometimes the heart rhythm is completely normal during the sensation. In other cases, premature beats, an arrhythmia or another medical condition is responsible. Understanding the pattern and associated symptoms is often more useful than assuming every palpitation has the same cause.
What Are the Most Common Causes of Heart Palpitations?
- Stress, anxiety, panic and strong emotions can increase heart rate and heartbeat awareness.
- Exercise normally increases heart rate, although unusual palpitations with exercise may need evaluation.
- Caffeine, nicotine, alcohol, energy drinks and recreational stimulants can trigger symptoms in some people.
- Medicines, including some decongestants, asthma medicines and other stimulants, can contribute.
- Hormonal changes during the menstrual cycle, pregnancy and menopause may be associated with palpitations.
- Medical conditions such as hyperthyroidism, anemia, fever and dehydration can cause a fast or noticeable heartbeat.
- PACs and PVCs commonly produce skipped, extra or thumping beats.
- Arrhythmias such as SVT, atrial fibrillation, atrial flutter and other abnormal rhythms can cause recurrent palpitations.
- Sometimes no clear cause is found, even after appropriate heart-rhythm evaluation.
Palpitations Are a Symptom — Not Automatically an Arrhythmia
A palpitation describes what you feel. An arrhythmia describes what the heart is doing electrically.
This means a person may experience palpitations while the heart rhythm is normal.
Another person may have palpitations because of PACs, PVCs, SVT, atrial fibrillation or another rhythm disorder.
An arrhythmia can even be present without causing any noticeable symptoms.
If you are unsure what your symptoms actually feel like, start with our heart palpitation symptoms guide .
Lifestyle and Emotional Causes of Heart Palpitations
Stress & Anxiety
Stress, anxiety and panic activate the body’s stress response, which can make the heart beat faster or more forcefully.
Read our detailed guide to anxiety and heart palpitations .
Exercise
Heart rate normally increases during physical activity.
However, unusual racing, irregularity, dizziness or fainting during exercise deserves medical attention.
Lack of Sleep
Fatigue and poor sleep may increase stress and make heartbeat sensations more noticeable.
Caffeine
Some people notice palpitations after coffee, tea, cola or energy drinks.
Individual sensitivity matters, and moderate coffee intake does not need to be universally prohibited.
Learn more about caffeine and palpitations .
Alcohol
Alcohol can influence heart rhythm, particularly at higher intakes. Binge drinking can trigger atrial fibrillation in susceptible people.
Nicotine & Stimulant Drugs
Nicotine and stimulant drugs such as cocaine and amphetamines can increase heart rate and contribute to arrhythmias.
Medical Conditions That Can Cause Palpitations
Palpitations are not always primarily a heart problem. Conditions elsewhere in the body can make the heart beat faster, harder or more noticeably.
Hyperthyroidism
Too much thyroid hormone can produce a rapid or irregular heartbeat, sweating, tremor, nervousness and weight loss.
See our guide to thyroid problems and heart palpitations .
Anemia
Anemia can cause palpitations together with fatigue, weakness, dizziness and shortness of breath.
Dehydration
Significant fluid loss can reduce circulating volume and lead to a faster heartbeat, weakness or dizziness.
Fever & Illness
Heart rate commonly rises during fever and acute illness. The faster heartbeat may be perceived as palpitations.
Electrolyte Abnormalities
Abnormal potassium, magnesium or other electrolyte levels can sometimes affect cardiac electrical activity.
This does not mean supplements should be taken without evidence of a deficiency or medical indication.
Low Blood Sugar
Hypoglycemia can activate stress hormones and may cause trembling, sweating, hunger and a fast or pounding heartbeat.
Menstrual Cycle, Pregnancy and Menopause
Hormonal and physiological changes can influence heartbeat awareness at different stages of life.
Menstrual Cycle
Some people notice palpitations at particular points in their cycle.
Heavy menstrual bleeding can also contribute to iron-deficiency anemia, which itself may cause palpitations.
Pregnancy
Pregnancy produces substantial cardiovascular and hormonal changes, and some pregnant people experience palpitations.
Persistent or concerning symptoms should still be discussed with the maternity or medical team.
Menopause
Palpitations may occur during perimenopause and menopause, sometimes around hot flushes, sleep disturbance or anxiety.
Heart-Rhythm Disorders That Can Cause Palpitations
Arrhythmias are an important cause of recurrent palpitations, but the exact rhythm cannot reliably be identified from sensation alone.
PACs
Premature atrial contractions are early beats arising from the upper chambers of the heart.
They may feel like an extra beat, skipped beat or sudden thump.
PVCs
Premature ventricular contractions arise from the ventricles and commonly produce a skipped-beat or thumping sensation.
Supraventricular Tachycardia
SVT often causes episodes of a rapid heartbeat that can begin and stop suddenly.
Atrial Fibrillation
AFib may cause a fast, irregular, fluttering or pounding heartbeat.
Some people with AFib, however, experience no palpitations.
Atrial Flutter
Atrial flutter can produce a fast heartbeat, palpitations, weakness, dizziness or shortness of breath.
Bradyarrhythmias
A slow or paused heartbeat can sometimes be perceived as irregular beats or palpitations, particularly when pauses are followed by stronger beats.
Read more about bradycardia and palpitations .
Can Other Heart Conditions Cause Palpitations?
Yes. Structural heart conditions can increase the likelihood of arrhythmias or cause symptoms that occur together with palpitations.
Heart Valve Disease
Valve disease may be associated with palpitations, breathlessness, fatigue, dizziness or chest symptoms.
Cardiomyopathy
Diseases affecting the heart muscle can increase the risk of abnormal rhythms in some patients.
Coronary or Other Heart Disease
Underlying cardiovascular disease can make palpitations more clinically significant and may change how they are evaluated.
Can Medication Cause Heart Palpitations?
Yes. Some medicines and supplements can affect heart rate or rhythm, while others may make the heartbeat more noticeable.
Examples that may be relevant in selected patients include:
- Some decongestants containing stimulants such as pseudoephedrine
- Some asthma medicines
- Thyroid hormone if the dose is excessive
- Stimulant medicines
- Certain supplements or energy products
- Recreational stimulant drugs
If symptoms began after starting or changing a medication, tell the prescribing clinician or pharmacist.
Do not stop a prescribed medicine simply because palpitations occur without first obtaining appropriate medical advice.
Our article on amoxicillin and heart palpitations shows why symptoms beginning during medication use do not always mean that the medicine is directly responsible.
You can also see our broader guide to medications and heart palpitations .
Can Eating, GERD, Gas or Hiatal Hernia Cause Palpitations?
Many patients notice palpitations around meals or at the same time as reflux, bloating or abdominal discomfort.
These patterns are worth recording, but they should not be explained by saying that ordinary stomach gas presses against the heart or that indigestion routinely irritates the vagus nerve and causes arrhythmia.
Instead, doctors consider meal size, caffeine, alcohol, medications, autonomic changes, digestive symptoms and independent heart-rhythm causes.
Start with our guide to heart palpitations after eating .
If reflux is prominent, see GERD and heart palpitations .
If abdominal fullness is a major feature, read bloating and palpitations .
Very large hiatal hernias are a separate situation because exceptionally large hernias can affect structures within the chest.
Position and Timing Can Provide Useful Clues
While Sitting
Quiet rest can make heartbeat sensations easier to notice.
While Lying Down
Some people notice palpitations more clearly in bed or in certain resting positions.
At Night or During Sleep
Nighttime symptoms may be easier to notice because the environment is quiet, although recurrent episodes may have other triggers.
Read heart palpitations at night .
What About “Vagus Nerve Irritation”?
The autonomic nervous system, including sympathetic and parasympathetic pathways, genuinely helps regulate heart rate.
However, it is not medically accurate to create a broad category of palpitations caused by “parasympathetic overstimulation” and then attribute it to:
- “Alkaline deficiency”
- Poor posture
- Ordinary bloating
- Indigestion
- Routine acid reflux
Those explanations are not established general mechanisms for heart palpitations.
The specific symptom pattern, medical history and recorded heart rhythm are much more useful when identifying the cause.
How Do Doctors Evaluate Heart Palpitations?
Testing is individualized. Not everyone with palpitations needs every cardiac test.
Medical History
Your clinician may ask what the heartbeat feels like, when it occurs, how long it lasts and what triggers it.
Medicines, caffeine, alcohol, supplements, family history and associated symptoms also matter.
Physical Examination
Pulse, heart rhythm, blood pressure and heart examination can provide important clues.
ECG / EKG
An electrocardiogram records the heart’s electrical activity.
It can identify many rhythm abnormalities if they are occurring while the ECG is being recorded.
Holter or Event Monitor
A normal short ECG does not exclude an intermittent arrhythmia.
Longer monitoring may help capture the rhythm during an actual palpitation episode.
Selected Blood Tests
Depending on the clinical history, doctors may consider testing for anemia, thyroid abnormalities, electrolytes or other medical causes.
Additional Testing When Indicated
Echocardiography, exercise testing or cardiology evaluation may be appropriate when the history, examination or ECG suggests a structural or rhythm problem.
The Word “Palpitation” Is Only the Beginning of the Diagnosis
When a patient tells me, “I have palpitations,” I do not yet know the cause.
I want to know: Does the heart suddenly race? Does it feel irregular? Is there one strong thump? Does it happen after coffee, eating or exercise? During anxiety? At night?
I also ask about thyroid symptoms, anemia, medications, pregnancy or hormonal changes, and whether dizziness, chest pain, breathlessness or fainting occurs.
Palpitations are a clue. The goal is to identify what is producing that clue rather than treating every patient as though they have the same condition.
When Should You See a Doctor for Palpitations?
Arrange medical assessment if palpitations:
- Are new or unexplained
- Keep returning
- Are becoming more frequent
- Last longer than before
- Feel very fast or clearly irregular
- Occur during exercise
- Are associated with significant dizziness or weakness
- Occur if you already have heart disease or an arrhythmia
If palpitations happen very frequently throughout the day, see our guide to constant heart palpitations .
If dizziness is a prominent symptom, read dizziness and heart palpitations .
When Heart Palpitations Need Urgent Care
Seek urgent or emergency medical care if palpitations occur with:
- Chest pain or significant chest pressure
- Fainting or loss of consciousness
- Severe shortness of breath
- Severe dizziness or near-fainting
- Sudden severe weakness
- A sustained very fast or severely irregular heartbeat with significant symptoms
- Other severe or rapidly worsening symptoms
Do not assume serious symptoms are caused by anxiety, caffeine, indigestion or another familiar trigger.
Causes of Heart Palpitations: FAQs
What is the most common cause of heart palpitations?
There is no single cause that explains every patient.
Common triggers include stress and anxiety, strenuous exercise, caffeine, nicotine, alcohol, medicines, fever and hormonal changes.
Premature beats and other arrhythmias are also important causes.
Can you have palpitations without an arrhythmia?
Yes. Palpitations describe the sensation of the heartbeat.
Heart-rhythm monitoring sometimes shows a normal rhythm while a person is experiencing palpitations.
Can anxiety cause heart palpitations?
Yes. Anxiety and panic can activate the body’s stress response and cause a faster or more forceful heartbeat.
However, new or concerning symptoms should not automatically be attributed to anxiety.
Can thyroid problems cause palpitations?
Yes. An overactive thyroid can cause an unusually fast or irregular heartbeat.
Other symptoms may include tremor, sweating, nervousness and weight loss.
Can anemia cause heart palpitations?
Yes. Anemia can cause a noticeable heartbeat together with tiredness, weakness, breathlessness and sometimes dizziness.
Can dehydration cause palpitations?
Significant dehydration can contribute to a faster heartbeat and may cause dizziness or weakness as well.
Can caffeine cause palpitations?
Some people are sensitive to caffeine and notice symptoms after coffee, tea, cola or energy drinks.
However, caffeine should not automatically be considered dangerous for everyone with palpitations.
Can hormone changes cause palpitations?
Yes. Palpitations may be noticed during the menstrual cycle, pregnancy and menopause.
Other contributors, including anemia and thyroid disease, should still be considered when appropriate.
Can GERD or gas cause palpitations?
GERD, gas, bloating and palpitations can occur together, particularly around meals.
But ordinary reflux or intestinal gas should not automatically be described as directly causing a heart arrhythmia.
Can a normal ECG miss the cause?
Yes. A standard ECG records only a short period.
If an arrhythmia occurs intermittently, it may not happen during the office ECG.
Holter or event monitoring may therefore be useful.
Related Heart Palpitation Guides
Evidence Used for This Article
- American Heart Association. Symptoms, Diagnosis and Monitoring of Arrhythmia .
- American Heart Association. Premature Contractions — PACs and PVCs .
- National Heart, Lung, and Blood Institute. Arrhythmias .
- Mayo Clinic. Heart Palpitations: Symptoms and Causes .
- NHS. Heart Palpitations .
- NHS. Hyperthyroidism: Symptoms .
- NHS. Iron-Deficiency Anaemia .