Skip to main content


Medically reviewed by Last updated on Mar 5, 2023.

What is myocarditis?

Myocarditis is an inflammation of the muscle of your heart (myocardium). The myocardium pumps blood through the heart and to other parts of the body. With myocarditis, the heart muscle can become damaged. This weakens the heart and makes it work harder. Over time, this may cause your heart to enlarge, lead to heart failure, and become life-threatening.

What increases the risk for myocarditis?

  • Viral, bacterial, fungal, or other infections
  • Alcohol or illegal drugs
  • Autoimmune conditions such as diabetes mellitus, lupus (SLE), or sarcoidosis
  • Medicines such as antibiotics, vaccines, or antidepressants
  • Chemotherapy or radiation therapy
  • Toxins, such as arsenic, lithium, or lead
  • Snake bites or insect stings

What are the signs and symptoms of myocarditis?

  • Joint or muscle pain, fever
  • Fatigue, dizziness, or fainting
  • Fast or irregular heartbeat
  • Chest pain or tightness
  • Shortness of breath

How is myocarditis diagnosed?

  • Blood tests will show if you have damage to the heart muscle and find the cause of myocarditis.
  • An EKG test records your heart rhythm and how fast your heart beats. It is used to check for an abnormal heart rhythm or damage to your heart.
  • A chest x-ray shows the size of your heart. It may also show if you have fluid around your heart or lungs.
  • An echocardiogram is a type of ultrasound. It shows the structure, movement, and valves and blood vessels of your heart.
  • An MRI takes pictures of your heart to show its size and check for any inflammation. You may be given contrast liquid to help the pictures show up better. Tell the healthcare provider if you have ever had an allergic reaction to contrast liquid. Do not enter the MRI room with anything metal. Metal can cause serious injury. Tell the healthcare provider if you have any metal in or on your body.
  • Nuclear imaging uses a radioactive dye injected into a blood vessel to show how your heart is working. The dye helps your healthcare provider see the pictures of your heart and blood vessels better. It may also show if you have inflammation or cause of myocarditis.
  • Cardiac catheterization is a procedure to find the cause of and treat a heart condition. A thin, flexible tube is inserted into a vein in your arm, neck, or groin and is moved into your heart. Contrast liquid may used so the pictures show up better on a monitor.
  • A biopsy is a small sample of your heart muscle that is sent to a lab for tests.

How is myocarditis treated?

  • Medicines may be given to lower your blood pressure, and strengthen or regulate your heart rate. You may also need medicine to decrease pain or excess fluid in your body. Medicine may also help to treat an infection or prevent your immune system from attacking your heart.
  • A heart device may be placed in your chest. It can help your heart beat and control your heart rate.
  • A heart transplant may be needed in rare cases if your condition is severe.

How can I manage my symptoms?

  • Limit physical activity. Your healthcare provider may suggest that you rest until your symptoms decrease. He or she may suggest that you avoid heavy lifting or certain physical activities. Ask what activities are safe for you, when to begin exercise, and the best exercise plan for you.
  • Eat heart-healthy foods. Eat foods that help protect the heart, including plenty of fruits and vegetables, nuts, and sources of fiber. Eat foods that contain healthy fats, such as walnuts, salmon, and canola and soybean oils. You may need to eat foods low in cholesterol or sodium (salt). You also may be told to limit saturated and trans fats.
  • Limit alcohol. Women should limit alcohol to 1 drink a day. Men should limit alcohol to 2 drinks a day. A drink of alcohol is 12 ounces of beer, 5 ounces of wine, or 1½ ounces of liquor.
  • Do not smoke. Nicotine and other chemicals in cigarettes can cause damage to your heart. Ask your healthcare provider for information if you currently smoke and need help to quit. E-cigarettes or smokeless tobacco still contain nicotine. Talk to your healthcare provider before you use these products.

What can I do to prevent the spread of germs?

  • Wash your hands often. Wash your hands several times each day. Wash after you use the bathroom, change a child's diaper, and before you prepare or eat food. Use soap and water every time. Rub your soapy hands together, lacing your fingers. Wash the front and back of your hands, and in between your fingers. Use the fingers of one hand to scrub under the fingernails of the other hand. Wash for at least 20 seconds. Rinse with warm, running water for several seconds. Then dry your hands with a clean towel or paper towel. Use hand sanitizer that contains alcohol if soap and water are not available. Do not touch your eyes, nose, or mouth without washing your hands first.
  • Cover a sneeze or cough. Use a tissue that covers your mouth and nose. Throw the tissue away in a trash can right away. Use the bend of your arm if a tissue is not available. Wash your hands well with soap and water or use a hand sanitizer.
  • Stay away from others while you are sick. Avoid crowds as much as possible.
  • Ask about vaccines you may need. Talk to your healthcare provider about your vaccine history. He or she will tell you which vaccines you need, and when to get them.
    • Get the influenza (flu) vaccine as soon as recommended each year. The flu vaccine is available starting in September or October. Flu viruses change, so it is important to get a flu vaccine every year.
    • Get the pneumonia vaccine if recommended. This vaccine is usually recommended every 5 years. Your provider will tell you when to get this vaccine, if needed.

Call your local emergency number (911 in the US) if:

  • You have any of the following signs of a heart attack:
    • Squeezing, pressure, or pain in your chest
    • You may also have any of the following:
      • Discomfort or pain in your back, neck, jaw, stomach, or arm
      • Shortness of breath
      • Nausea or vomiting
      • Lightheadedness or a sudden cold sweat

When should I call my doctor?

  • Your signs and symptoms come back or get worse.
  • You have a fever.
  • You have chills, a cough, or feel weak and achy.
  • You have questions or concerns about your condition or care.

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 healthcare providers to decide what care you want to receive. You always have the right to refuse treatment. The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.

© Copyright Merative 2023 Information is for End User's use only and may not be sold, redistributed or otherwise used for commercial purposes.

Further information

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