When Your Heart Suddenly Starts Racing, Here’s What to Know

There are a few things that can get your attention faster than your own heartbeat.

You may be sitting on the couch, lying in bed, or getting ready for work when suddenly you become very aware of your heart. It may feel like it is pounding, fluttering, racing, or beating differently than usual. Sometimes it feels as though your heart has skipped a beat, followed by an uncomfortable pause before the next beat.

And almost immediately, your mind goes to the same question:

Is something wrong with my heart?

This is where things can become confusing.

Heart palpitations are common, and many are harmless. They can happen after too much coffee, during a stressful period, when you are dehydrated, or due to changes elsewhere in the body. But palpitations can also sometimes be related to an abnormal heart rhythm or another medical condition that deserves attention.

The important question is not simply whether you are experiencing palpitations.

It is what is happening around them.

When did they start? How long do they last? What were you doing when they occurred? And, perhaps most importantly, are there other symptoms happening at the same time?

Let's talk about what your racing heart may be trying to tell you.

What Are Heart Palpitations?

Heart palpitations are simply the sensation of being unusually aware of your heartbeat.

You may notice your heart pounding in your chest, fluttering, racing, or skipping a beat. Some people describe extra beats or a sudden thumping sensation that they can feel in their chest, throat, or neck.

Palpitations can last only a few seconds or continue for much longer. They may happen during exercise, when you are under stress, or even when you are completely relaxed and doing nothing.

That unpredictability can make them especially unsettling.

The sensation itself does not necessarily tell us whether something serious is happening. We have to look at the bigger picture, including your medical history, medications, symptoms, and the pattern of the palpitations.

Common Causes of Palpitations

There are many possible reasons you may suddenly become aware of your heartbeat. Some are temporary and relatively simple to address. Others may require investigation.

1. Caffeine

Coffee is one of the first things people think about, and for good reason. Caffeine can increase heart rate and make some people more aware of their heartbeat.

But coffee is not the only source. Caffeine is also found in tea, energy drinks, pre-workout products, some soft drinks, and certain medications or supplements.

If your palpitations started around the same time you increased your caffeine intake, that is useful information. It does not automatically prove that caffeine is the cause, but it gives your physician an important piece of the puzzle.

2. Stress and Anxiety

Yes, anxiety can cause palpitations.

When you are stressed, your body releases hormones such as adrenaline. These hormones prepare your body to respond to a perceived threat by increasing your heart rate and making your heartbeat more noticeable.

You may notice palpitations during a difficult period at work, after an upsetting event, before an important appointment, or during a period of ongoing anxiety.

But there is an important caveat here.

We should not automatically assume that every racing heart is anxiety.

If your palpitations are new, keep coming back, are becoming more intense, or are

accompanied by symptoms such as chest pain, fainting, significant dizziness, or shortness of breath, they deserve an appropriate medical assessment.

Sometimes anxiety is the explanation. Sometimes it is not.

3. Dehydration

Your heart may also respond when your body lacks enough fluid.

Dehydration can occur during hot weather, after intense exercise, during an illness, or simply when you have not been drinking enough throughout the day. Vomiting and diarrhea can make the problem worse and may also lead to changes in electrolytes.

When fluid levels drop, your heart may beat faster to help maintain adequate circulation.

If your palpitations occur alongside thirst, weakness, dizziness, dark urine, or recent fluid loss, dehydration may be part of the picture.

4. Anemia and Iron Deficiency

Your blood carries oxygen throughout your body. When your blood's ability to carry oxygen is reduced, your heart may have to work harder to meet your body's needs.

This can happen with anemia, including iron-deficiency anemia.

Palpitations accompanied by fatigue, weakness, dizziness, or shortness of breath may prompt your physician to investigate. Heavy menstrual bleeding is another important detail to mention because it can contribute to iron deficiency and anemia.

Sometimes the heart responds to a problem elsewhere in the body.

5. Thyroid Problems

Your thyroid plays an important role in regulating metabolism and many other body functions.

An overactive thyroid can cause a faster heart rate or palpitations. You may also notice

symptoms such as tremor, sweating, heat intolerance, anxiety, frequent bowel movements, or unexplained weight loss.

This is one reason bloodwork may be considered when someone has unexplained or persistent palpitations.

6. Hormonal Changes

Hormonal changes can also affect how your heartbeat feels.

Pregnancy, perimenopause, and menopause can all be associated with changes in heart rate or an increased awareness of your heartbeat. For some women, palpitations occur alongside hot flashes, sleep disruption, changes in menstrual cycles, or mood symptoms.

However, new palpitations should not automatically be blamed on hormones.

Hormones may be contributing, but your physician still needs to consider the overall clinical picture.

7. Medications and Supplements

Sometimes the cause is hiding in your medicine cabinet.

Certain medications can increase heart rate or trigger palpitations. These may include some cold medications, asthma medications, stimulants, and other prescription or non-prescription products.

Supplements count too.

When your physician asks what you are taking, include vitamins, herbal products, pre-workout supplements, energy products, and other over-the-counter products. Something that seems harmless because it is available without a prescription may still affect your heart rate.

8. Abnormal Heart Rhythms

Sometimes palpitations really are coming from the heart itself.

Abnormal heart rhythms, also called arrhythmias, range from relatively benign extra beats to conditions such as atrial fibrillation and other rhythm disturbances that may require treatment.

This is where the pattern becomes particularly important.

How fast was your heart beating? Did it feel regular or irregular? Did the episode begin and end suddenly, or did your heart gradually speed up? How long did it last? Were you exercising or resting? Did you feel dizzy, weak, or faint?

These details can help your physician decide whether additional testing is needed.

When Should You Worry About Heart Palpitations?

Most occasional palpitations are not medical emergencies. Still, certain symptoms warrant attention and should not be ignored.

1. Palpitations With Chest Pain or Pressure

A racing or irregular heartbeat accompanied by significant chest pain, pressure, or tightness needs urgent assessment.

If you have symptoms that could indicate a heart attack or another medical emergency, call 911.

Do not wait to see whether the symptoms disappear.

2. Palpitations With Fainting

Losing consciousness during or shortly after palpitations is particularly important.

Fainting has many possible causes, but when it occurs alongside palpitations, we have to consider whether a cardiovascular problem could be involved.

That combination deserves prompt medical evaluation.

3. Severe Shortness of Breath

There is a difference between becoming aware of your breathing during a stressful moment and struggling to breathe.

Significant difficulty breathing, particularly when accompanied by palpitations, chest pain, fainting, or significant weakness, requires urgent medical attention.

4. Palpitations During Exercise

Your heart is supposed to beat faster when you exercise. That is a normal response.

However, sudden racing, an irregular rhythm, fainting or near-fainting, chest pain, or unusual shortness of breath during exertion should be assessed.

Do not assume that symptoms occurring during exercise are simply a sign that you need to improve your fitness.

5. A Family History of Sudden Cardiac Death

Family history matters.

Tell your physician if a close relative died suddenly or unexpectedly at a young age, particularly if there was a known or suspected heart condition.

This information can significantly change how we approach cardiac symptoms and whether further evaluation is appropriate.

6. New Palpitations With Significant Dizziness

Feeling your heart skip a beat for a second is different from having sustained palpitations while feeling as though you might pass out.

If your heart is racing and you are significantly dizzy or feel like you may lose consciousness, that combination deserves medical attention.

What Will Your Doctor Do?

A good assessment starts with your story.

Your physician will want to understand what the palpitations actually feel like and what is happening when they occur. You may be asked:

    ● When did the palpitations start?

    ● How often do they happen, and how long do they last?

    ● Do they begin and stop suddenly?

    ● Do they occur at rest or during exercise?

    ● Are they associated with chest pain, dizziness, fainting, or shortness of breath?

    ● How much caffeine do you consume?

    ● What medications, vitamins, and supplements are you taking?

    ● Are you experiencing heavy menstrual bleeding?

    ● Could you be pregnant?

    ● Are you experiencing symptoms that could suggest a thyroid problem?

    ● Is there a family history of heart disease or sudden cardiac death?

Your pulse, blood pressure, and cardiovascular examination can provide additional clues.

An electrocardiogram, commonly called an ECG, may also be performed. The challenge is that an ECG only captures what your heart is doing at that particular moment.

If your palpitations are intermittent, your ECG may look completely normal because the

abnormal rhythm simply isn't occurring while the tracing is being recorded.

In those situations, your physician may consider longer heart rhythm monitoring to capture what happens during an episode.

Depending on your symptoms and medical history, bloodwork may also be appropriate. This can help investigate possible contributors such as anemia, iron deficiency, or thyroid problems.

The goal is not to order every test for every person.

It is important to ask the right questions first and then choose testing based on the individual patient.

Your Smartwatch Can Be Helpful, But It Isn't Your Doctor

Wearable devices have changed the way many people think about their heart rhythm.

If your smartwatch records your heart rate during an episode, that information can be useful. Some devices can also record a limited ECG.

Bring that information to your physician when appropriate.

But remember that a smartwatch alert is not a diagnosis. And the absence of an alert does not guarantee that everything is normal.

Your device can provide useful information, but it cannot replace a medical assessment.

If you are experiencing concerning symptoms, do not wait for your watch to tell you whether you need medical attention.

Pay Attention to Patterns

If your palpitations come and go, keeping a simple record can be surprisingly helpful.

Consider noting:

     ● When the episode happened

     ● How long did it last

     ● What were you doing at the time

     ● your heart rate, if you know it

     ● How many caffeine or energy drinks did you have that day

     ● Medications or supplements you took

     ● Whether you experienced dizziness, chest pain, shortness of breath, or other  

        symptoms

You do not need a complicated spreadsheet.

A simple note on your phone may be enough.

Sometimes the pattern tells us almost as much as the symptom itself. A palpitation that

consistently occurs after an energy drink tells a different story from one that repeatedly begins during exercise or occurs with dizziness and near-fainting.

Details matter.

Don't Panic, But Don't Ignore Your Body Either

Feeling your heart suddenly race can be frightening. I understand why people worry when it happens.

Fortunately, many palpitations have relatively harmless explanations. Your second cup of coffee, a stressful week, dehydration, hormonal changes, or another temporary factor may be enough to make you suddenly notice every beat of your heart.

But common does not mean every episode should automatically be dismissed.

You do not need to become afraid of every skipped beat. At the same time, you should not talk yourself out of seeking care when something feels different, persistent, or concerning.

The goal is not fear.

The goal is awareness.

Pay attention to changes. Notice the pattern. Know the warning signs. And when something does not feel right, let a healthcare professional help you put the symptom into context.

At Bonsai Medical & Aesthetics, we believe symptoms deserve context because your body rarely tells its story through a single symptom.

Sometimes a racing heart is nothing more than too much caffeine or a stressful week.

Sometimes it is a sign that something else needs attention.

Listen to your body, but do not let fear write the story.

Get the right information. Ask the right questions. And when you need to, get checked.

Because taking your symptoms seriously does not mean expecting the worst. It means giving yourself the best chance of understanding what is happening and knowing what to do next.

Book a Consultation at Bonsai Medical & Aesthetics

If you are experiencing new, recurrent, or unexplained heart palpitations, Dr. Tomi Mitchell can help assess the possible causes and determine whether further evaluation is appropriate.

Ready to get your symptoms checked?

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Disclaimer

This article is for informational purposes only and does not constitute medical advice. It is not intended to diagnose, treat, or cure any condition. Always seek guidance from a qualified healthcare provider about your health.

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