What Causes Palpitations?

Many things can cause palpitations. You may feel palpitations even when your heart is beating normally or somewhat faster than normal. In these cases, nothing is wrong with your heart.

However, some palpitations are a sign of an actual heart problem. Sometimes, the cause of palpitations can’t be found.

If you start having palpitations, you should see your doctor to have them checked out.

Causes Not Related to Heart Problems

Strong Emotions

You may feel your heart pounding or racing during anxiety, fear, or stress. You also may have these feelings if you’re having a panic attack.

Vigorous Physical Activity

Intense activity can make it feel as though your heart is beating too hard or fast, even though it's working normally. It also may cause an occasional premature (extra) heartbeat.

Medical Conditions

Certain medical conditions can cause palpitations. This is because they can make the heart beat faster or stronger or cause premature (extra) heartbeats. These conditions include:

• An overactive thyroid
• A low blood sugar level
• Anemia
• Some types of low blood pressure
• Fever
• Dehydration (not enough fluid in the body)

Hormonal Changes

The hormonal changes that happen during pregnancy, menstruation, and the perimenopausal period can sometimes cause palpitations. These palpitations will likely improve or go away as these conditions go away or change.

Some palpitations that occur during pregnancy may be due to anemia.

Medicines and Stimulants

A number of medicines can trigger palpitations because they can make the heart beat faster or stronger or cause premature (extra) heartbeats. These include:

• Asthma inhalers.
• Medicines to treat an underactive thyroid. (Too much thyroid replacement hormone, used to treat an underactive thyroid, can cause palpitations by causing an overactive thyroid.)
• Medicines to prevent arrhythmias. (Medicines used to treat these irregular heartbeats can sometimes cause other irregular heart rhythms.)

Over-the-counter medicines that act as stimulants also may cause palpitations. These include decongestants (found in cough and cold medicines) and some herbal or nutritional supplements.

Caffeine, nicotine (found in tobacco), alcohol, and illegal drugs (such as cocaine and amphetamines) also may cause palpitations.

Causes Related to Heart Problems

Sometimes, palpitations are the symptoms of arrhythmias. Arrhythmias are problems with the speed or rhythm of the heartbeat. However, less than half of the people who have palpitations have arrhythmias.

During an arrhythmia, the heart can beat too fast, too slow, or with an irregular rhythm. An arrhythmia happens when some part of the heart’s electrical system doesn’t work as it should.

Palpitations are more likely to be related to an arrhythmia if you:

• Have had a heart attack or are at risk for one.
• Have heart disease or risk factors for heart disease.
• Have other heart problems, such as heart failure, heart valve problems, or heart muscle problems.
• Have abnormal electrolyte levels. Electrolytes are minerals, such as potassium and sodium, found in blood and body fluids. They're vital for normal health and functioning of the body.