Appendicitis is the infection of the appendix, a small section of the large intestine. Infection can arise if the appendix becomes blocked by stool, a foreign body, or cancer. Although it can occur at any age, appendicitis is rare under age 2 and most common between ages 10 and 30.

The classic symptoms of appendicitis include:
Dull pain near the upper abdomen that becomes sharp as it moves to the lower right abdomen. This is usually the first sign.
Loss of appetite
Nausea and/or vomiting soon after abdominal pain begins
Abdominal swelling
Inability to pass gas

Surgery is often performed on individuals with appendicitis to remove the appendix. This does not cause any apparent consequences. A course of antibiotics is often given alongside surgical treatment.