Heart palpitations are usually caused by premature heartbeats, which are almost always harmless. The two most common types are premature atrial contractions and premature ventricular contractions, and most people experience them at some point. That said, palpitations have a long list of possible triggers, from caffeine and stress to hormonal shifts and thyroid problems, so pinning down your specific cause takes some detective work.
What You’re Actually Feeling
Under normal conditions, you don’t notice your heartbeat at all. Palpitations happen when something changes your heart’s rate or rhythm, creating an abnormal movement in the chest that your body registers as a flutter, skip, or pounding sensation.
The most common culprit is an extra beat firing slightly too early. What’s interesting is that you probably aren’t feeling the extra beat itself. When that premature beat fires, it blocks the next normal beat and gives your heart a longer pause to fill with blood. The beat that follows is stronger than usual because it’s pumping a larger volume, and that forceful thump is what you perceive as a “skipped” beat. It’s actually the opposite: a bigger-than-normal beat after a brief pause.
People vary enormously in how much they notice these events. Some are aware of virtually every premature beat, while others are completely unaware of even complex rhythm disturbances. If you’re someone who tends to notice every heartbeat, that heightened awareness itself can make palpitations feel more alarming than they are.
Common Triggers You Can Control
Stimulants are the most obvious place to start. Caffeine in usual amounts (a couple of cups of coffee) does not appear to increase the risk of abnormal heart rhythms for most people. Energy drinks with very high caffeine doses are a different story and worth avoiding if you’re palpitation-prone. Alcohol is a clearer trigger: studies and randomized trials show that alcohol in the blood makes the heart more likely to develop irregular rhythms, and experts recommend no more than three alcoholic drinks per week for people susceptible to rhythm problems.
Nicotine, whether from cigarettes or vaping, stimulates the same fight-or-flight pathways that speed up the heart and can provoke extra beats. Decongestants found in cold and sinus medications also act as stimulants to the heart. If you’ve recently started taking a new over-the-counter cold remedy and noticed palpitations, that connection is worth exploring.
Beyond substances, everyday factors matter too. Sleep deprivation, dehydration, intense exercise, and emotional stress all raise adrenaline levels and can set off episodes. Many people find their palpitations cluster during high-stress periods or after a poor night’s sleep, then disappear once the trigger resolves.
Medications That Can Cause Palpitations
Several prescription and over-the-counter drug classes are known to provoke or worsen irregular heart rhythms. Bronchodilators used for asthma (like albuterol inhalers) work by stimulating the same receptors that speed up the heart. ADHD medications like methylphenidate are indirect stimulants that can trigger episodes in some people. Nasal decongestants containing pseudoephedrine or phenylpropanolamine act on the same pathways.
Recreational drugs carry especially high risk. Amphetamines, methamphetamine, cocaine, and MDMA (ecstasy) all flood the nervous system with signals that push the heart into faster, more chaotic rhythms. If palpitations started or worsened after beginning any new medication, that’s important information to share with your doctor.
Hormonal Shifts and Palpitations
Fluctuating hormone levels are one of the most common causes of palpitations in women, particularly during three windows: around menstruation, during pregnancy, and through menopause. Big surges in reproductive hormones can make the heart more electrically excitable, which lowers the threshold for extra beats. Many women first experience palpitations during perimenopause and find they fade once hormone levels stabilize after menopause is complete.
Thyroid Problems and Other Medical Causes
An overactive thyroid gland produces excess thyroid hormone, which forces the heart to beat harder and faster. It can also trigger abnormal rhythms in the heart’s upper chambers, causing a racing, skipping, or fluttering sensation. If your palpitations come with unexplained weight loss, heat intolerance, trembling hands, or anxiety that feels disproportionate to your circumstances, a thyroid problem is worth investigating. A simple blood test can confirm or rule it out.
Anemia (low red blood cell count, often from iron deficiency) is another medical cause. When your blood carries less oxygen, the heart compensates by beating faster, which you may feel as pounding or racing. Heavy menstrual periods, poor dietary iron intake, or chronic blood loss can all lead to anemia severe enough to cause palpitations. Again, a routine blood test picks this up easily.
Less commonly, structural heart conditions, electrolyte imbalances (particularly low potassium or magnesium), and fever can trigger palpitations.
Red Flags That Need Immediate Attention
Most palpitations are benign, but certain combinations of symptoms point to something more serious:
- Sudden collapse or loss of consciousness during an episode requires emergency care immediately.
- Dizziness or lightheadedness accompanying a racing heart suggests the rhythm disturbance is affecting blood flow to the brain.
- Chest pain alongside palpitations may indicate the heart isn’t getting enough oxygen during the abnormal rhythm.
- Family history of sudden cardiac death at a young age or inherited heart conditions raises the risk that palpitations reflect a genetic rhythm disorder rather than a harmless extra beat.
Palpitations that last only a few seconds and resolve on their own, without any of the symptoms above, are rarely dangerous. Episodes that persist for minutes, happen frequently, or come with lightheadedness deserve evaluation.
How Palpitations Are Diagnosed
The challenge with palpitations is that they’re often gone by the time you get to a doctor’s office. A standard electrocardiogram (EKG) captures your heart’s electrical activity for about 10 seconds, which is useful only if the abnormal rhythm happens to occur during that snapshot. For most people, portable monitoring is needed.
A Holter monitor is a small device you wear for 24 to 48 hours. It records every heartbeat continuously, and your doctor compares the data against a diary you keep of when symptoms occurred. This works well for palpitations that happen at least once a day.
If your episodes are less frequent, an event monitor is more practical. You wear it for up to 30 days, and it continuously records but only saves data when you press a button during symptoms. It captures 30 seconds before and after you press, so even if there’s a slight delay in your reaction, the relevant rhythm is preserved.
Your doctor will also likely order blood tests to check thyroid function, electrolyte levels, and red blood cell counts, since these are simple, treatable causes that are easy to identify or rule out.
What Helps Reduce Episodes
For the majority of people whose palpitations are benign, management comes down to identifying and minimizing triggers. Keeping a simple log of when episodes happen, what you ate or drank beforehand, how much sleep you got, and your stress level can reveal patterns that aren’t obvious in the moment.
Practical steps that consistently help: cutting back on alcohol (ideally to three or fewer drinks per week), limiting caffeine to moderate amounts, staying hydrated, prioritizing consistent sleep, and managing stress through whatever works for you, whether that’s exercise, breathing techniques, or reducing commitments. If a medication is the likely trigger, your doctor can often switch you to an alternative that’s less likely to affect heart rhythm.
For people whose palpitations are frequent and bothersome despite lifestyle changes, or for those with an identified rhythm disorder, targeted treatments exist that range from medication to procedures that correct the electrical pathway causing the problem. The right approach depends entirely on what the monitoring reveals about your specific rhythm pattern.