Heart palpitations are moments when you become unusually aware of your heartbeat. You might feel it fluttering, pounding, racing, or seemingly skipping a beat. Most of the time, palpitations are harmless and pass on their own, but they can occasionally signal an underlying heart rhythm problem or a treatable medical condition worth investigating.
What’s Actually Happening in Your Heart
Your heart has a built-in electrical system that keeps it beating in a steady rhythm. A cluster of cells called the SA node acts as a natural pacemaker, sending electrical signals that tell each chamber when to contract. Your nervous system fine-tunes the speed: the “fight or flight” branch speeds things up, while the “rest and digest” branch slows things down.
Palpitations happen when something disrupts this electrical timing. The most common culprits are premature contractions, essentially extra beats that fire slightly too early. These can start in the upper chambers of the heart (premature atrial contractions, or PACs) or the lower chambers (premature ventricular contractions, or PVCs). After that early beat, there’s usually a brief pause before the next normal beat, and that next beat hits harder than usual. That’s the “thud” or “skipped beat” sensation most people describe. PACs and PVCs are extremely common and, in most people, completely benign.
Common Triggers
A wide range of everyday factors can set off palpitations. Caffeine is one of the most frequently blamed, though research from the British Heart Foundation shows that moderate caffeine intake doesn’t cause abnormal heart rhythms in most people. Some individuals are simply more sensitive to it, and for them, even a cup or two of coffee can trigger that fluttering feeling. Alcohol, nicotine, and decongestant medications are other common stimulants that can nudge the heart into extra beats.
Beyond substances, physical triggers include dehydration, lack of sleep, intense exercise, and eating a heavy meal. Fever and illness can also temporarily raise your heart rate enough to make you notice it pounding.
Stress, Anxiety, and the Fight-or-Flight Response
Anxiety is one of the most common non-cardiac causes of palpitations, and the mechanism is straightforward. When you feel stressed or anxious, your autonomic nervous system activates the fight-or-flight response. This floods your body with adrenaline, which directly speeds up the SA node and increases your heart rate. You may feel your heart racing or pounding even though the rhythm itself is perfectly normal.
This creates a frustrating feedback loop. You notice your heart beating fast, which makes you more anxious, which keeps your heart rate elevated. Panic attacks can produce especially intense palpitations that mimic the feeling of a cardiac event, including chest tightness and shortness of breath. Recognizing this pattern doesn’t mean you should ignore palpitations, but it does explain why many people who seek medical evaluation for them receive reassuring results.
Hormonal and Nutritional Causes
Hormonal shifts can make palpitations more likely during specific life stages. During menopause, fluctuating estrogen levels are one of the most common causes of new-onset palpitations. Many women notice their heart racing at the same time as a hot flash. Pregnancy and the days around menstruation can also bring surges in hormones that trigger extra beats. As estrogen declines during menopause, you also lose some of its protective effects on heart function, which is worth discussing with your doctor if palpitations become frequent.
Low levels of key minerals can also disrupt heart rhythm. Potassium plays a direct role in the electrical signaling that makes heart muscle cells contract and relax. When potassium drops too low, it can cause skipped beats, an irregular heartbeat, or in severe cases, a dangerous arrhythmia. Low magnesium levels make potassium deficiency more likely and can independently affect heart rhythm. Thyroid disorders, particularly an overactive thyroid, are another well-known metabolic cause. If your palpitations are new, persistent, or worsening, a simple blood test can check for these issues.
When Palpitations Point to Something Serious
While most palpitations are harmless, certain accompanying symptoms signal that something more serious may be happening. The Mayo Clinic identifies three key warning signs that warrant emergency care: chest pain lasting more than a few minutes, dizziness or fainting, and shortness of breath. These combinations can indicate a significant arrhythmia, a problem with blood flow to the heart, or another condition that needs immediate evaluation.
Palpitations that last several minutes at a time, happen frequently without an obvious trigger, or come with a very fast heart rate (consistently above 150 beats per minute at rest) also deserve medical attention. A history of heart disease, heart surgery, or a family history of sudden cardiac death raises the stakes and lowers the threshold for getting checked out.
How Palpitations Are Diagnosed
The challenge with diagnosing palpitations is that they’re often gone by the time you’re sitting in a doctor’s office. That’s why the diagnostic process usually involves more than one step.
An electrocardiogram (EKG) is typically the first test. It’s quick and painless: sticky patches placed on your chest record your heart’s electrical activity for about 10 seconds. An EKG can catch a rhythm problem if it’s happening in that moment, but it often comes back normal because palpitations are intermittent.
If the EKG doesn’t capture anything, the next step is usually a Holter monitor, a portable device you wear for 24 to 48 hours while going about your daily life. It continuously records your heart rhythm, giving your doctor a much longer window to spot irregularities. If your palpitations happen less than once a week, an event recorder may be a better fit. You wear it for up to 30 days and press a button when you feel symptoms, which marks that moment in the recording for your doctor to review.
What You Can Do During an Episode
If you’re in the middle of a palpitation episode and it feels like your heart is racing, a technique called the Valsalva maneuver can sometimes reset your rhythm. Here’s how it works: sit down or lie on your back, take a breath, then push that breath out against your closed mouth and nose while straining as if you’re trying to have a bowel movement. Hold for 15 to 20 seconds, then release and breathe normally. This stimulates the vagus nerve, which activates the “rest and digest” branch of your nervous system and can slow a racing heart.
Other vagal maneuvers include splashing cold water on your face, coughing forcefully, or bearing down. These work best for episodes of supraventricular tachycardia (a specific type of fast rhythm originating in the upper chambers) and may not help with every type of palpitation, but they’re safe to try.
Reducing Palpitations Over Time
For palpitations driven by lifestyle triggers, the most effective approach is identifying and managing your personal triggers. Keeping a simple log of when episodes happen, what you were doing, what you consumed, and how much sleep you got the night before can reveal patterns surprisingly quickly. Some people find that cutting back on alcohol makes a bigger difference than reducing caffeine. Others discover that sleep deprivation is their primary trigger.
Staying well hydrated, managing stress through regular physical activity, and addressing anxiety (whether through therapy, breathing techniques, or other approaches) all reduce the frequency of benign palpitations. If a nutritional deficiency is contributing, correcting it with dietary changes or supplements can resolve the problem entirely. For the small percentage of people whose palpitations stem from a structural heart problem or a persistent arrhythmia, treatments range from medication to procedures that target the misfiring electrical pathways directly.