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Chemical Cardioversion


Chemical cardioversion is medicine given to correct arrhythmias. An arrhythmia is when your heart beats too fast or irregularly. It may prevent your body from getting the blood and oxygen it needs. Your heart has 4 chambers called the atria and ventricles. The atria are at the top of your heart, and the ventricles are at the bottom of your heart. Most arrhythmias that need cardioversion start in the atria.


The week before your procedure:

  • Do not take any aspirin or ibuprofen before the cardioversion, unless your caregiver tells you to. Keep taking your other medicines as directed by your caregiver.
  • Bring your medicine bottles or a list of your medicines when you see your caregiver. Tell your caregiver if you are allergic to any medicine. Tell your caregiver if you use any herbs, food supplements, or over-the-counter medicine.
  • Tell your caregiver if you know or think you might be pregnant.
  • You may need to have blood and urine tests done before your cardioversion. Ask your caregiver for more information about these and other tests that you may need. Write down the date, time, and location of each test.
  • Write down the correct date, time, and location of your procedure.

The day before your procedure:

Ask caregivers about directions for eating and drinking.

The day of your procedure:

  • Ask your caregiver before taking any medicine on the day of your procedure. These medicines include insulin, diabetic pills, high blood pressure pills, or heart pills. Bring a list of all the medicines you take, or your pill bottles, with you to the hospital.
  • Do not use lotions or ointments on your chest or back. This may cause problems with the sticky patches of the heart monitor.
  • If you wear contact lenses, do not wear them on the day of your procedure or surgery. Glasses may be worn.
  • Ask a family member or friend to be available to drive you home when you leave the hospital.

Informed consent

is a legal document that explains the tests, treatments, or procedures that you may need. Informed consent means you understand what will be done and can make decisions about what you want. You give your permission when you sign the consent form. You can have someone sign this form for you if you are not able to sign it. You have the right to understand your medical care in words you know. Before you sign the consent form, understand the risks and benefits of what will be done. Make sure all your questions are answered.


What will happen:

  • Caregivers will place sticky patches on your chest to hook you up to a heart monitor to watch your heart rhythm. You will have one or more IVs placed in your arm. You may be given oxygen through a mask or through small plastic prongs that fit just inside your nose. You may also need blood thinners or other medicines before and during the procedure.
  • You may feel warm or flushed when the chemical cardioversion medicine is put into your IV. You may get a headache or feel lightheaded or dizzy. You may have pain, tightness, or pressure in your chest, neck, back, shoulders, arms, or jaw. You may feel nauseated, short of breath, or scared. These symptoms are normal, and usually last for just a few seconds. Your caregiver may tell you to cough during the procedure. You may need more than one dose of medicine to help your heart rhythm return to normal.
  • If the chemical cardioversion medicine does not work, caregivers may suggest that you have an electrical cardioversion. Electrical cardioversion is when electric pads or paddles are used to give your heart an electric shock. This shock may reset the heart and return it to a normal beat. Medicine is usually given first to help you relax before this procedure. Ask your caregiver for more information about electrical cardioversion if you are told that you need one.

After the procedure:

You may need to stay in the hospital. You may need to take medicine to help your heart beat in a regular rhythm.


  • You cannot make it to your cardioversion appointment on time.
  • You ate or drank something less than 8 hours before the procedure.
  • You have a fever.
  • You think your heart rhythm problems are getting worse.
  • You have questions or concerns about your cardioversion or heart rhythm problem.

Seek Care Immediately if

  • Your heart is fluttering or jumping.
  • You feel lightheaded, or you fainted.
  • You have chest pain when you take a deep breath or cough. You cough up blood.
  • You have discomfort in your chest that feels like squeezing, pressure, fullness, or pain.
  • You have pain or discomfort in your back, neck, jaw, stomach, or arm.
  • You have weakness or numbness in part of your body.
  • You have sudden trouble breathing.
  • You become confused or have difficulty speaking.
  • You have dizziness, a severe headache, or vision loss.


Chemical cardioversion may cause other heart or blood pressure problems. Even with cardioversion, your heart may not return to or stay in a normal rhythm. Some arrhythmias may cause a blood clot to form in your heart. The clot may travel to other parts of your heart or brain and cause life-threatening problems, such as a heart attack or stroke. If untreated, some arrhythmias can increase your risk of heart failure or a heart attack.

Care Agreement

You have the right to help plan your care. Learn about your health condition and how it may be treated. Discuss treatment options with your caregivers to decide what care you want to receive. You always have the right to refuse treatment.

Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

Learn more about Chemical Cardioversion (Precare)

Micromedex® Care Notes