What is appendicitis?

Your appendix is a finger-sized tube located where the large and small intestines connect. It has no known function, but if it gets inflamed or infected (appendicitis), you’ll need immediate treatment.

An inflamed appendix may cause pain off and on. Or it may burst open (rupture), causing sudden, severe pain. A ruptured appendix can spread bacteria through the abdominal cavity. These bacteria trigger a serious, sometimes-fatal infection called peritonitis.

Where is your appendix?

The appendix is in the lower right side of the abdomen (belly).

How common is appendicitis?

Approximately 5% of Americans will develop appendicitis. It’s the No. 1 cause of abdominal pain requiring surgery .

Who might get appendicitis?

Appendicitis can occur at any age, although it’s most common in people in their teens and 20s. Appendicitis in children most often occurs during the tween or teen years. But even elementary school-age children get appendicitis.

What causes appendicitis?

It’s not clear what brings on appendicitis. Something triggers an inflammation (irritation and swelling) or infection in your appendix. Causes could include:

What are the symptoms of appendicitis?

Severe abdominal pain in the lower right belly — where your appendix is — is a key sign of appendicitis. Symptoms often come on suddenly and get worse. They include:

  • Abdominal pain or tenderness that hurts more when you cough, sneeze, inhale or move.
  • Swollen belly.
  • Constipation.
  • Diarrhea.
  • Inability to pass gas.
  • Loss of appetite (not feeling hungry when you usually would).
  • Low-grade fever (below 100 degrees F).
  • Nausea and vomiting.

Last reviewed by a Cleveland Clinic medical professional on 07/06/2020.


  • American Academy of Family Physicians (AAFP). Appendicitis. Accessed 7/9/2020.
  • American Pediatric Surgical Association. Acute (Early) Appendicitis. Accessed 7/9/2020.
  • Merck Manual. Appendicitis. Accessed 7/9/2020.
  • National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Appendicitis. Accessed 7/9/2020.

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