A fast heartbeat of over 100 beats per minute can happen for various reasons, including drug reactions, alcohol, stress, and some health conditions. If the cause is unclear, the heart may seem to beat fast for no reason.

According to the American Heart Association (AHA), the average adult has a resting heartbeat of about 60⁠–⁠100 beats per minute. A heart rate higher than 100 beats per minute is known as tachycardia.

Most causes of a rapid heartbeat are not dangerous. However, a faster than usual heartbeat can be a symptom of an underlying health problem.

This article looks at what can cause a person’s heart to beat faster, treatments, and when to see a doctor.

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Stressful emotions, such as anxiety, anger, and fear, can cause a person’s heart rate to increase.

When the body experiences stress, the adrenal glands release epinephrine, or adrenaline. The body has two adrenal glands, one on top of each kidney.

The body uses epinephrine to prepare a person for immediate action. Epinephrine can cause a person to experience:

  • increased heart rate
  • increased blood pressure
  • enlarged pupils
  • palpitations, where the heart rate can increase, decrease, or feel like it has skipped a beat
  • sweating
  • anxiety

Generally, a person should find that their symptoms decrease once they no longer feel stress.

Treatment

A person who experiences stressful emotions regularly may be at risk of developing certain conditions. The American Psychological Association (APA) note that chronic stress can increase a person’s chances of developing certain conditions, such as high blood pressure, heart attack, or stroke.

A person may be able to manage their stress in the following ways:

  • exercising regularly
  • engaging in relaxing activities, such as meditation or massage
  • setting goals and priorities
  • speaking to friends and family for emotional support or help
  • talking with a doctor or healthcare provider

Substances that can cause a person’s heartbeat to speed up include:

Caffeine

Caffeine is a stimulant found in many drinks, such as coffee, tea, certain sodas, and energy drinks. Caffeine powder is also available as a dietary supplement.

The Food & Drug Administration (FDA) suggest that an adult could have up to 400 milligrams (mg) of caffeine per day, which is around 4 or 5 cups of coffee. However, the amount of caffeine a person can consume without adverse effects depends on their caffeine sensitivity.

A person who has too much caffeine may experience:

Alcohol

A study from 2014 found that even a small amount of alcohol can increase a person’s chances of developing atrial fibrillation. Atrial fibrillation is a condition that causes a person’s heart to beat irregularly and sometimes abnormally fast.

A further study from 2017 tested people’s breath for alcohol concentration levels. Researchers found that as a person’s alcohol concentration level increased, so did their heart rate.

Nicotine

Nicotine is a highly addictive chemical found in cigarettes. According to the AHA, nicotine can cause increased blood pressure and heart rate.

Research from 2016 noted that nicotine could increase a person’s heart rate by 10⁠–⁠15 beats per minute (BPM). Researchers also pointed out that a person’s heart rate and blood pressure increased regardless of whether the nicotine was smoked, inhaled, or ingested.

Illegal stimulants

Illegal stimulants, such as cocaine and amphetamines, can cause a person to have a higher heart rate.

Research from 2014 found that people who use cocaine were more likely to experience irregular or increased heart rates.

Doctors sometimes use amphetamines to treat people who have ADHD or narcolepsy. However, amphetamines can cause a series of side effects, including:

Certain medications

According to the United Kingdom’s National Health Service (NHS), certain medications can cause a person to have an irregular heartbeat. These medications include:

Certain supplements

Certain herbal supplements can increase a person’s heart rate, such as:

Bitter orange: People might use bitter orange for heartburn, nasal congestion, weight loss, appetite suppression or stimulation, and athletic performance. Certain studies state that it can cause rapid heartbeat; however, the results were inconclusive.

Valerian: Valerian is a supplement used for anxiety, insomnia, depression, premenstrual syndrome, headache, and menstrual issues. Side effects of taking valerian can include heart disturbances, such as a rapid heartbeat, headache, upset stomach, uneasiness, excitability, mental dullness, and insomnia.

Ginseng: Ginseng is promoted as a general tonic to improve wellbeing. However, ginseng has side effects that can include increased heartbeat, insomnia, menstrual problems, breast pain, headache, digestive problems, and high or low blood pressure.

Treatment

A person who experiences an increased heart rate due to caffeine, alcohol, nicotine, or illegal stimulants should try reducing the amount they consume.

If a person is dependent on a particular drug, they should consider speaking to a healthcare worker or counselor to discuss treatment options.

If a person has a rapid heart rate after taking certain medications or supplements, they can speak to their doctor to see if there is an alternative medication they can take.

An increase in heart rate may occur during pregnancy. This can happen because the heart has to pump blood to the placenta and around the body.

A study from 2019 found that, on average, a pregnant person’s heart rate increased by 7–⁠8 beats per minute (bpm). The same study also found that the average heart rate increased throughout pregnancy. A person’s average heart rate at 10 weeks was 79.3 bpm, which increased to 86.9 bpm by 40 weeks.

Additionally, once a person goes through menopause, they have an increased risk of coronary heart disease. The British Heart Foundation notes that a person in the postmenopausal phase of their life may feel that their heart is racing.

Treatment

A person who is pregnant or postmenopausal should speak with their doctor if they are concerned about their increased heart rate.

Learn about HRT here.

Electrolytes are minerals and salts in a person’s blood. Electrolytes help conduct electrical impulses around a person’s body.

A person who has an imbalance of electrolytes may notice they have an increased heart rate. An older study from 2013 found that the most common symptoms a person with an electrolyte imbalance experienced were:

  • shortness of breath
  • fever
  • rapid heartbeat
  • confusion
  • bloating
  • irregular heartbeat

Treatment

To diagnose an electrolyte imbalance, a doctor can perform an electrolyte test. An electrolyte test checks the levels of electrolytes in a person’s blood. The doctor can then recommend treatment based on what electrolyte levels are abnormal.

Learn which foods contain the most electrolytes here.

A fast heart rate is not usually a cause for concern. However, an increase in heart rate may indicate that a person has an underlying health problem. Health problems that can cause rapid heart rate include:

A person should speak to a doctor if:

  • they have a history of heart problems
  • the increased heart rate goes on for a long time or gets worse
  • their increased heart rate is causing them concern

A person should seek immediate medical attention if they experience:

  • shortness of breath
  • dizziness or lightheadedness
  • fainting
  • blackouts
  • tightness in their chest
  • chest pain

A person can experience an increased heart rate for many reasons. Certain conditions can cause a person to have a rapid heartbeat, but they are not usually serious.

If a person is concerned about their fast heart rate, they should speak to a doctor. A person should seek immediate medical help if they experience any troubling symptoms.