October 28, 2026

Palpitations Causes: What Triggers a Racing or Fluttering Heart

Palpitations are the feeling that your heart is racing, pounding, fluttering or skipping a beat. Most of the time they come from everyday triggers such as stress, anxiety, exercise, caffeine, nicotine, alcohol or a decongestant. Less often they point to a heart rhythm problem or a valve condition that deserves a proper check. This guide walks through the common causes, the ones tied to meals, nighttime and medicines, and the signs that mean you should call a provider or 911.

Garden State Medical Group

Get Heart Palpitations Checked

Garden State Medical Group offers primary care and cardiopulmonary services for patients in North Bergen and Secaucus.

Visit Garden State Medical Group

TL;DR

Palpitations are a symptom, not a diagnosis. Stress, anxiety, caffeine, nicotine, alcohol, exercise and some medicines are the most common triggers.
Heart rhythm problems such as atrial fibrillation, and valve problems such as mitral valve prolapse, can also cause palpitations, so new or changing episodes should be checked.
Palpitations after meals and at night are often linked to food, alcohol, stress or simply noticing your heartbeat more when it is quiet.
Call 911 if palpitations come with chest pain, shortness of breath, dizziness, unusual sweating or fainting.

What palpitations actually are
The most common causes
When the cause is the heart itself
Why palpitations happen after eating
Why palpitations happen at night
Can medicines like Lexapro cause palpitations?
How palpitations are evaluated
When to call 911 and when to book a visit
What you can do at home while you wait for answers
Our perspective
Get your palpitations checked in North Bergen or Secaucus
FAQ
Sources

What palpitations actually are

The American Heart Association describes palpitations as a symptom, not a diagnosis. That matters, because the word covers very different experiences. Some people feel a single hard thump. Others feel a flutter in the chest, throat or neck, or a run of fast beats that lasts a few seconds or a few minutes.

The sensation does not always match what the heart is doing. The same American Heart Association article notes that some people feel palpitations even when monitoring shows a completely normal rhythm. So a strong feeling does not prove something is wrong, and a normal reading on a single day does not always explain what you felt. That is why doctors pay close attention to when the episodes happen, how long they last and what else you notice at the time.

The most common causes

MedlinePlus lists the usual culprits: stress, anxiety, panic attacks, exercise, caffeine, nicotine, alcohol and certain medicines such as decongestants. Here is how each one tends to show up.

Stress, anxiety and panic

When you are anxious, your body releases adrenaline, which speeds up the heart and makes each beat feel stronger. A panic attack can bring a pounding heart along with sweating, trembling and a sense of dread. Poor sleep and ongoing worry can keep the system on edge, so palpitations may come in clusters during stressful weeks. If this sounds familiar, our article on how stress affects your heart explains the connection in more detail.

Caffeine, nicotine and alcohol

These are stimulants or rhythm irritants, and they are the easiest causes to test. Coffee, energy drinks, pre-workout powders, cigarettes, vaping and even a few drinks in an evening can set off extra beats. If you notice palpitations an hour or two after a large coffee or a night out, try cutting back for a couple of weeks and see whether the episodes fade.

Exercise and fever

Your heart should beat faster during a workout, and you may notice it more than usual. A fever also raises your heart rate. These are normal responses, and the feeling should settle as you rest or the fever breaks.

Medicines and supplements

Decongestants are a classic trigger, and the same goes for some asthma inhalers, thyroid medicine taken at too high a dose and stimulant products sold as diet or energy aids. Illegal stimulants such as cocaine and methamphetamine are also well known causes. Bring every medicine and supplement you take to your visit, including over-the-counter products, because the cause is sometimes sitting in the medicine cabinet.

Dehydration, low blood sugar and electrolytes

The American Heart Association lists electrolyte problems among the causes of the sensation. Heavy sweating, vomiting, diarrhea, skipping meals or not drinking enough fluid can all change the balance of minerals and sugar that your heart depends on. A blood test can check these levels.

Hormonal changes

Pregnancy, the days before a period and the transition to menopause can all change how aware you are of your heartbeat, and many people notice more flutters at those times. Heart rhythm problems also occur in women, so if palpitations are frequent, last a long time or come with other symptoms, do not assume hormones are the only reason.

When the cause is the heart itself

Palpitations can also come from the heart’s electrical system or structure. MedlinePlus says they may be due to an abnormal heart rhythm caused by heart disease or an abnormal heart valve, such as mitral valve prolapse.

The American Heart Association also names premature contractions and arrhythmias such as atrial fibrillation among the causes. Premature beats are early extra beats that feel like a skip or a thud, and they are very common. Atrial fibrillation is an irregular, often fast rhythm that raises the risk of stroke over time, which is why a new irregular heartbeat should be evaluated rather than ignored.

These patterns raise the level of concern:

Episodes that are new, different from your usual ones or becoming more frequent
A fast, steady or irregular pulse that starts and stops suddenly
Existing heart disease, high blood pressure, diabetes or a family history of heart rhythm problems
Symptoms that appear during exertion rather than at rest

If you also have swelling or fast weight gain, read our guide to the heart failure signs caregivers should know.

Why palpitations happen after eating

Heart palpitations after eating are searched more than almost any other version of this symptom, and there are several plausible explanations. WebMD notes that some people get palpitations after heavy meals rich in carbohydrates, sugar or fat, and that foods high in MSG, nitrates or sodium can bring them on too. If the same food keeps causing it, a food sensitivity may be involved.

Other meal-related triggers are easy to overlook:

Coffee, tea or soda with the meal. The caffeine may be the real cause.
Alcohol with dinner. Even modest amounts can set off extra beats in some people.
A very large meal. Blood flow shifts toward digestion and you may feel your pulse more, especially when you lie down soon afterward.
Blood sugar swings. A sugary meal followed by a drop can leave you shaky with a racing heart.
Reflux. Heartburn and chest discomfort can be hard to tell apart from heart symptoms.

A simple food and symptom diary for two weeks is useful. Write down what you ate, when, and how you felt in the following hour. If the episodes come with chest pain, shortness of breath or lightheadedness, do not wait to see a pattern. Get urgent care.

Why palpitations happen at night

Many people first notice their heartbeat when they lie down. The room is quiet, nothing else competes for your attention, and you may be pressing your chest against a pillow or lying on your left side. The British Heart Foundation also points out that nighttime is when people are more likely to dwell on stressful events, which can heighten how strongly you perceive a heartbeat.

Practical causes to check first:

Caffeine late in the day
Alcohol in the evening, which can disturb sleep and rhythm
A large late meal
Poor or interrupted sleep, and stress carried into bed
A new medicine taken in the evening

If palpitations wake you from sleep, happen with snoring and pauses in breathing, or come with breathlessness, mention it to your provider. Sleep problems and rhythm problems can overlap, and the right test depends on the full picture.

Can medicines like Lexapro cause palpitations?

Some can. Escitalopram (Lexapro) is an antidepressant that WebMD says may rarely cause a dangerous rhythm problem called QT prolongation. The risk is higher in older adults, in people with a personal or family history of heart rhythm conditions, and in those taking other medicines that affect heart rhythm.

This is not a reason to stop an antidepressant on your own. Stopping suddenly can cause its own problems. If you are on Lexapro or any similar medicine and notice new palpitations, fainting or a feeling that you might pass out, call your prescriber promptly and say exactly what you are feeling. They may check an EKG and your potassium and magnesium levels, and may adjust the plan.

How palpitations are evaluated

A good evaluation starts with questions: when did it start, how long does it last, what were you doing, and what do you take. Then testing is chosen to match your story.

Exam and blood pressure. Your provider listens to your heart and checks for valve sounds or an irregular pulse.
Blood tests. These can look for anemia, thyroid problems, blood sugar and electrolyte issues.
EKG. A quick, painless recording of your heart’s electrical activity. It captures only the moments it runs, so it is most helpful if you have symptoms at that time.
Holter monitor. A small wearable recorder that tracks your rhythm as you go about your day, useful when episodes come and go.
Echocardiogram or stress test. These look at the heart’s structure and how it responds to exertion, when the history suggests they are needed.

Because the feeling can occur even when the recorded rhythm is normal, repeated monitoring may still be reasonable if your symptoms continue. If you want to understand how assessment can work when palpitations are felt despite a normal recording, a heart health test is one example of how people approach it. Whatever route you take, bring the results to a clinician who can interpret them alongside your history.

When to call 911 and when to book a visit

The cautions here follow MedlinePlus.

Call 911 or your local emergency number if palpitations come with fainting or loss of consciousness, chest pain, shortness of breath, unusual sweating, or dizziness or lightheadedness.

Contact your provider if any of these apply:

You have never had palpitations before
They are new or different from what you usually feel
You often feel extra heartbeats
You have heart disease or risk factors for it
You notice a sudden increase or change
Your pulse is above 100 beats per minute without exercise, anxiety or fever

The American Heart Association adds that palpitations lasting minutes or hours, or that make you feel you may pass out, should be evaluated sooner rather than later. For a deeper look at the decision, see our post on when to worry and when to wait. If your blood pressure is also very high with symptoms, read when a high blood pressure reading is an emergency.

What you can do at home while you wait for answers

These steps are reasonable for occasional, mild palpitations with no warning signs:

Cut back on caffeine, nicotine and alcohol and see whether episodes change.
Drink water through the day and do not skip meals.
Keep a log with the date, time, length, what you were doing and what you ate or took.
Check your pulse when it happens: count beats for 30 seconds and double it, and note whether it feels regular.
Practice slow breathing or take a short walk when you feel anxious.
Review your medicines and supplements with a provider or pharmacist.

That log is one of the most valuable things you can bring to an appointment, because palpitations rarely happen on cue in an exam room.

Our perspective

Our perspective — overview diagram

At Garden State Medical Group, we see palpitations from two sides. Many patients in North Bergen and Secaucus arrive frightened by a symptom that turns out to be linked to caffeine, stress, poor sleep or a medicine. Others have a rhythm or valve problem that no one has found yet. We do not think anyone should have to guess which group they belong to.

Our approach is to listen first, then test with purpose. Because our primary care and cardiopulmonary teams work with on-site diagnostics, an EKG or other heart testing can often be part of the same care plan rather than a separate referral to find elsewhere. We also look beyond the heartbeat itself at sleep, stress, blood sugar, thyroid health and medicines, since these so often drive the symptom. Our aim is to give you a clear answer and a plan you can follow, whether that is a lifestyle change, ongoing monitoring or treatment.

— Garden State Medical Group

Get your palpitations checked in North Bergen or Secaucus

If your palpitations are new, frequent or worrying you, start with our primary care team, who can take your history and arrange testing. If you already know you have a heart or lung condition, our cardiopulmonary care specialists can follow your rhythm and symptoms over time. You can see the full list of on-site diagnostic tests we offer, or reach us through our website to book an in-person or telemedicine visit. We accept Medicare and Medicaid, and you can confirm other accepted plans when you book.

FAQ

Are heart palpitations dangerous?

Most are not. Stress, caffeine and exercise are common harmless causes. They become a concern when they come with chest pain, shortness of breath, fainting or dizziness, or when you have heart disease. In those cases, get care right away.

Why do I get heart palpitations after eating?

Heavy meals high in carbohydrates, sugar or fat can bring them on, as can foods rich in MSG, nitrates or sodium. Caffeine, alcohol and reflux are other common meal-time triggers. A two-week food diary helps you and your provider spot the pattern.

Can palpitations come from anxiety alone?

Yes. Anxiety and panic release adrenaline, which speeds and strengthens the heartbeat. Even so, a first episode, or a change from your usual pattern, is worth having checked so a rhythm problem is not missed.

Can Lexapro cause heart palpitations?

Escitalopram may rarely cause a rhythm problem called QT prolongation, especially in older adults or people with heart rhythm conditions. Do not stop it on your own. Call your prescriber if you notice new palpitations or a feeling you might faint.

What test finds the cause of palpitations?

It depends on your symptoms. An EKG records a single moment, a Holter monitor records over a day or more, and blood tests can find thyroid, sugar or electrolyte problems. Your provider chooses based on how often the episodes happen.