What palpitations feel like
Palpitations are when you suddenly become aware of your own heartbeat. People describe them in different ways:
- a thud, or a feeling that the heart has "skipped" or "missed" a beat
- a fluttering in the chest, throat or neck
- a pounding or forceful heartbeat
- a racing heart, sometimes starting and stopping suddenly
- an irregular, chaotic heartbeat
They may last a second or two, or go on for minutes or hours. They can happen at rest, at night, after eating, or during exercise. How they start and stop, how fast they are and whether they are regular are all useful clues to the cause.
Are palpitations serious?
Most of the time, no. The most common causes are harmless extra beats (ectopic beats), or a normal heart speeding up in response to anxiety, caffeine, alcohol, exercise or illness.
Less often, palpitations are caused by a heart rhythm problem such as atrial fibrillation, atrial flutter or supraventricular tachycardia (SVT). These are usually very treatable, but it is important to diagnose them, because some carry a risk of stroke or can affect how well the heart pumps over time.
Call 999 or go to A&E if palpitations come with:
- chest pain or tightness
- severe breathlessness
- fainting, or feeling that you are about to faint
- a very fast heartbeat that does not settle
When to get palpitations checked
See your GP or a cardiologist if:
- your palpitations are frequent, getting worse, or last more than a few minutes
- they bring on dizziness or breathlessness, or happen during exercise
- your heartbeat feels irregular, or a smartwatch has flagged a possible irregular rhythm
- you already have a heart condition, high blood pressure or diabetes
- someone in your family died suddenly, especially under the age of 40, or has an inherited heart condition
How doctors work out the cause
The description of your symptoms is the most useful clue. Palpitations that start and stop suddenly suggest an abnormal rhythm such as SVT. A fast, irregular beat suggests atrial fibrillation. A single thud or pause suggests ectopic beats. A heartbeat that speeds up gradually, with stress or exercise, is usually a normal rhythm. An ECG taken during symptoms gives the answer; if symptoms are infrequent, a heart monitor worn for days or weeks can capture them.
How we find the cause
The key is to record your heart rhythm during symptoms. Your consultation starts with a detailed history, which often points to the likely cause. We then arrange the right tests, such as an ECG, a heart rhythm monitor worn for 24 hours to several days, an echocardiogram (heart scan) and blood tests. Read more about the tests.
Helpful things to bring to your appointment
- A note of when your palpitations happen, how long they last, and what you were doing
- Your pulse rate during an episode, and whether it felt regular or irregular
- Any ECG recordings from a smartwatch or personal ECG device
- A list of your medicines, including supplements and anything bought over the counter
Palpitations in particular situations
- Palpitations at night
- Palpitations after eating
- Palpitations and anxiety
- Palpitations in pregnancy
- Palpitations and the menopause
- My smartwatch says I might have AF
- When palpitations need urgent help
Common questions
Can palpitations be caused by dehydration?
Yes. Low fluid levels and low salt can make the heart beat faster, especially on standing. Drinking enough usually helps.
Are palpitations a sign of a heart attack?
Rarely on their own. Palpitations with chest pain, breathlessness or sweating need a 999 call.
How long do palpitations last?
From a single missed beat to several hours. Note how long yours last: it helps with diagnosis.
Can medicines cause palpitations?
Yes, including decongestants, asthma inhalers, thyroid medicines, some antidepressants and ADHD medicines. Don't stop a prescribed medicine without advice.
Medically reviewed by Dr Aftab Gill, Consultant Interventional Cardiologist (GMC 4499826). Last reviewed October 2026. This page gives general information and is not a substitute for personal medical advice.