People with diabetes who take certain glucose-lowering medications can experience episodes of low blood sugar.

The body's response to falling glucose levels can include the release of adrenaline, which may cause:

• Shaking

• Sweating

• Hunger

• Anxiety

• Rapid heartbeat

• Weakness

• Dizziness

Nighttime low blood sugar can be particularly concerning because a person may be asleep when symptoms begin.

If you have diabetes and repeatedly wake with sweating, shakiness, confusion, or a racing heartbeat, discuss the pattern with your healthcare professional.

13. Anemia Can Make Your Heart Work Harder

Anemia occurs when the blood doesn't have enough healthy red blood cells or hemoglobin to adequately carry oxygen.

Depending on the cause and severity, anemia may lead to:

• Fatigue

• Weakness

• Shortness of breath

• Dizziness

• Headaches

• A faster heartbeat

• Awareness of heartbeats

Iron deficiency is one possible cause of anemia, but there are many others.

If palpitations are accompanied by persistent fatigue, pale skin, shortness of breath, or weakness, a blood test may help identify whether anemia is involved.

14. Heart Rhythm Problems Can Also Cause a Pounding Heart

Not every palpitation is caused by stress or lifestyle.

Sometimes the heart's electrical rhythm becomes abnormal.

Examples include:

• Atrial fibrillation

• Supraventricular tachycardia

• Premature atrial contractions

• Premature ventricular contractions

• Other arrhythmias

These conditions can produce sensations such as:

• Fluttering

• Skipping

• Pounding

• Racing

• Pausing followed by a stronger beat

• Irregular heartbeat

Some abnormal rhythms are relatively harmless, while others require medical evaluation.

The sensation alone usually cannot tell you which one is occurring.

Why a “Skipped Beat” Can Feel Like a Hard Beat

This is something that surprises many people.

Sometimes what feels like a powerful heartbeat is actually a premature beat followed by a brief pause and then a stronger beat.

You may perceive it as:

Beat → pause → THUMP

The stronger beat can feel dramatic even though the underlying rhythm disturbance may be brief.

Occasional premature beats can occur in healthy people, particularly with caffeine, stress, lack of sleep, alcohol, or other triggers.

However, frequent or persistent palpitations should be discussed with a healthcare professional.

When Is a Pounding Heart More Concerning?

Occasional awareness of your heartbeat, especially when you're lying quietly in bed, isn't necessarily dangerous.

But certain symptoms should not be ignored.

Seek urgent medical attention if a rapid, pounding, or irregular heartbeat occurs with:

• Chest pain or pressure

• Severe shortness of breath

• Fainting or near-fainting

• Severe dizziness

• New confusion

• Significant weakness

• A sustained very rapid heartbeat

• Symptoms that are rapidly worsening

These symptoms can have multiple causes, including potentially serious cardiovascular problems.

Don't assume that they are simply anxiety.

What If Your Heart Pounds but Your Pulse Is Normal?

This is an important distinction.

You can sometimes feel your heartbeat strongly without having an unusually fast pulse.

For example, you might measure a normal resting heart rate but still feel each beat prominently.

This can happen because heartbeat awareness depends not only on the number of beats per minute but also on:

• Strength of contraction

• Body position

• Stress level

• Attention

• Chest anatomy

• Recent exercise

• Stimulants

• Individual sensitivity

If you repeatedly notice strong heartbeats but your pulse is normal, it may still be useful to mention the symptom during a medical visit—especially if it is new.

What Can You Do When It Happens at Night?

If you notice your heart pounding but have no emergency symptoms, try to stay calm and observe what's happening.

Sit up or change position

If lying on one side makes the sensation stronger, changing position may reduce your awareness of it.

Take slow, controlled breaths

Slow breathing can help reduce sympathetic nervous system activation when stress is contributing.

Check your pulse

If you know how, measure your pulse for about 30–60 seconds.

Pay attention to:

• Approximate rate

• Whether it feels regular

• Whether there are obvious pauses or irregularities

Avoid repeatedly checking your pulse every few seconds, because excessive monitoring can increase anxiety.

Think about potential triggers

Ask yourself:

• Did I drink coffee late today?

• Did I consume an energy drink?

• Did I drink alcohol?

• Did I exercise intensely?

• Have I been sleeping poorly?

• Am I dehydrated?

• Did I eat a large meal shortly before bed?

• Am I particularly stressed?

• Did I take a new medication or supplement?

Identifying a recurring pattern can be valuable.

Keep a Simple Symptom Diary

If nighttime palpitations happen repeatedly, keeping a short record can help.

Write down:

Time: When did it happen?

Duration: How long did it last?

Heart rate: If measured, approximately how fast was it?

Rhythm: Did it feel regular, irregular, fluttering, or like skipped beats?

Position: Were you lying on your back, left side, or right side?

Food and drinks: What did you consume during the previous several hours?

Caffeine: How much and when?

Alcohol: How much and when?

Symptoms: Any dizziness, chest discomfort, breathlessness, sweating, or faintness?

This information can be surprisingly useful during a medical appointment.

Tests a Healthcare Professional May Consider

If palpitations are persistent or unexplained, a healthcare professional may begin with a physical examination and medical history.

Depending on the symptoms, possible tests can include:

Electrocardiogram (ECG/EKG)

An ECG records the heart's electrical activity and can identify certain rhythm abnormalities.

Holter or other ambulatory monitor

If symptoms come and go, a portable monitor may record the heart rhythm over an extended period.

Blood tests

Depending on the situation, testing may evaluate things such as:

• Thyroid function

• Blood counts

• Electrolytes

• Other metabolic factors

Additional cardiac evaluation

If there are concerning symptoms or abnormal findings, additional testing may be recommended.

The appropriate evaluation depends on the individual's symptoms and medical history.

Common Myths About Nighttime Heart Palpitations

Myth 1: Feeling your heartbeat always means you have heart disease.

Reality: Heartbeat awareness can occur for many reasons, including stress, caffeine, body position, dehydration, and normal variations in heartbeat.

Myth 2: If your heart pounds at night, it's probably anxiety.

Reality: Anxiety can certainly cause palpitations, but other causes—including medications, thyroid problems, anemia, and abnormal rhythms—are also possible.

Myth 3: A normal pulse means the symptom doesn't matter.

Reality: You can have a normal heart rate while still experiencing noticeable palpitations. Persistent or concerning symptoms should still be discussed with a healthcare professional.

Myth 4: You should drink a lot of water immediately before bed.

Reality: Adequate hydration is important, but consuming a large amount of fluid right before sleep can increase nighttime urination and disrupt sleep.

Myth 5: All skipped beats are dangerous.

Reality: Occasional premature beats can occur in healthy people, but frequent, sustained, or symptomatic irregular heartbeats should be evaluated.

The Bottom Line

Feeling your heart pound at night doesn't necessarily mean something is wrong with your heart.

When you're lying quietly in bed, you may simply become more aware of sensations that were less noticeable during the day. Body position, stress, caffeine, alcohol, dehydration, poor sleep, large meals, and other everyday factors can all contribute.

At the same time, recurring palpitations can sometimes be associated with conditions such as thyroid disorders, anemia, medication effects, or abnormal heart rhythms.

The most important factors are what the sensation feels like, how long it lasts, how often it happens, and whether it occurs with other symptoms.

If it is occasional and disappears quickly without other concerning symptoms, keeping track of potential triggers may be useful.

But if the pounding is new, frequent, persistent, or accompanied by chest pain, severe shortness of breath, fainting, severe dizziness, or a sustained rapid heartbeat, seek medical evaluation promptly.

Your heartbeat is something you're supposed to notice occasionally.

The goal isn't to fear every unusual sensation - but to recognize when a recurring pattern deserves a closer look.