Heart palpitations can occur at any time, including during rest and sleep. In many cases, they are harmless. However, nighttime palpitations can sometimes be associated with stress, caffeine, alcohol, medications, sleep disruption, or an underlying heart rhythm problem.
Sleep disorders may also play a role. In particular, sleep apnea can place significant stress on the cardiovascular system and is associated with abnormal heart rhythms, including atrial fibrillation.
Understanding why palpitations happen at night can help you determine when they may simply be noticeable—and when they deserve medical attention.
Heart palpitations are the sensation of being unusually aware of your heartbeat. You may feel like your heart is:
Palpitations are a symptom rather than a diagnosis. They can occur with a normal heart rhythm or with an abnormal rhythm called an arrhythmia.
You may actually experience palpitations during the day without noticing them.
During the daytime, your attention is often focused on work, conversations, exercise, or other activities. At night, however, you're lying quietly in bed with fewer distractions.
Your sleeping position can sometimes change how strongly you perceive your heartbeat. Some people notice palpitations more when lying on their side or in certain positions.
This does not necessarily mean that anything is wrong with your heart.
There are many potential causes of nighttime palpitations.
Stress activates the body's sympathetic nervous system, which is responsible for the "fight-or-flight" response.
If you're lying in bed worrying about work, finances, relationships, health, or the next day, your body may remain in a heightened state of alertness.
A racing or pounding heartbeat is a common symptom of panic attacks. The sensation can be particularly frightening when it happens unexpectedly at night.
Anxiety can also create a cycle:
Breaking this cycle may require addressing both anxiety and sleep problems.
Caffeine is a stimulant that can increase alertness and, in some people, contribute to palpitations.
Coffee is not the only potential source. Caffeine can also be found in:
Even if you drink caffeine several hours before bed, some caffeine may remain in your system when you're trying to sleep.
If you regularly experience nighttime palpitations, consider tracking when you consume caffeine and whether your symptoms occur afterward.
Alcohol may initially make you feel sleepy, but it can interfere with sleep later in the night.
It may also contribute to palpitations in some people. Alcohol use is one of several factors associated with nighttime palpitations.
Dehydration can affect cardiovascular function and may contribute to palpitations.
Electrolytes—including potassium and magnesium—also play important roles in normal heart rhythm.
Drinking water may help if dehydration is contributing, but recurring or unexplained palpitations should still be evaluated by a healthcare professional.
Certain medications can cause or contribute to palpitations.
Potential examples include some:
If your palpitations began after starting a new medication or supplement, talk with your healthcare provider before making any changes.
Poor sleep can affect the cardiovascular system in several ways.
Sleep deprivation and irregular sleep may influence stress hormones, blood pressure, metabolism, and autonomic nervous system activity.
The relationship can also work in the opposite direction: palpitations may repeatedly wake you up or make you anxious about falling asleep.
For some people, nighttime palpitations and poor sleep can become a cycle:
Palpitations → anxiety → difficulty sleeping → sleep deprivation → increased stress → more noticeable palpitations
Breaking that cycle may require identifying what is causing the palpitations in the first place.
One of the most important connections between sleep and cardiovascular health is obstructive sleep apnea.
Sleep apnea causes repeated interruptions in breathing during sleep. These episodes can cause changes in oxygen levels, blood pressure, and autonomic nervous system activity.
Sleep-disordered breathing is associated with cardiac arrhythmias, including atrial fibrillation and other rhythm disturbances. The American Heart Association identifies sleep-disordered breathing as an important cardiovascular risk factor and notes its relationship with cardiac arrhythmias.
Many people with sleep apnea do not remember waking up when their breathing is interrupted.
Instead, they may notice:
Loud snoring or witnessed pauses in breathing can also be important clues.
Learn more about sleep apnea and other sleep disorders evaluated at Anchorage Sleep Center.
It can be associated with episodes of increased cardiovascular activation during nighttime breathing disturbances.
When breathing is repeatedly disrupted, the body responds to changes in oxygen and carbon dioxide and activates the sympathetic nervous system. This can produce noticeable changes in heart rate and blood pressure.
If your heart frequently races immediately after waking, particularly if you also:
it may be worth discussing sleep apnea with a healthcare professional.
Most palpitations are not dangerous, but it depends on what is causing them.
Occasional skipped or extra beats can occur in healthy people. Premature atrial contractions and premature ventricular contractions are common examples.
However, palpitations can sometimes be caused by an arrhythmia or another medical condition.
Make an appointment with a healthcare professional if your palpitations:
An evaluation may include a medical history, physical examination, electrocardiogram, blood tests, or heart-rhythm monitoring depending on your symptoms.
Palpitations should not automatically be attributed to anxiety or poor sleep.
Call 911 or seek emergency medical care if palpitations occur with:
The American Heart Association recommends urgent evaluation when palpitations occur with symptoms such as chest pain, shortness of breath, dizziness, or fainting.
If your palpitations have been medically evaluated and no serious cause has been identified, lifestyle and sleep habits may help reduce triggers.
Consider moving coffee, energy drinks, and other caffeinated beverages earlier in the day.
If you notice palpitations after drinking, reducing alcohol intake may help.
Drink fluids consistently throughout the day rather than waiting until bedtime.
Going to bed and waking at approximately the same time each day can support your circadian rhythm and overall sleep health.
Try a calming activity before bedtime, such as:
If you become anxious about your heart rate, repeatedly checking your pulse or wearable device may increase your awareness and anxiety.
If your symptoms are new or concerning, medical evaluation is more useful than repeatedly checking your heart rate yourself.
If palpitations occur alongside poor-quality sleep, it may be worth looking beyond the heart itself.
A sleep evaluation may be appropriate if you experience palpitations along with:
Anchorage Sleep Center offers diagnostic testing and treatment for a range of sleep disorders.
Heart palpitations at night can be alarming, but they are not always a sign of a serious heart problem. Stress, anxiety, caffeine, alcohol, dehydration, medications, and simply being more aware of your heartbeat at night can all contribute.
However, recurrent nighttime palpitations should not automatically be dismissed as anxiety or poor sleep. Sleep disorders—particularly sleep apnea—are associated with cardiovascular stress and abnormal heart rhythms.
If you regularly wake up with your heart racing, especially if you also snore, gasp, wake frequently, or feel exhausted during the day, talk with a healthcare professional about whether a sleep disorder could be contributing.
Contact Anchorage Sleep Center to learn more about sleep evaluations and treatment options.
This article is intended for educational purposes only and should not replace professional medical advice, diagnosis, or treatment. Heart palpitations can have many causes. Seek emergency medical attention for palpitations accompanied by chest pain, severe shortness of breath, fainting, severe dizziness, or other concerning symptoms.
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