Appendicitis is one of the causes of serious belly pain. It happens when the appendix, a part of the large intestine, becomes infected and inflamed.

Appendicitis is most common in people between the ages of 10 and 30, although it can occur at any age. Common symptoms of appendicitis include:

• Pain in the belly. The pain may begin around the belly button.
• Pain in the belly that gets stronger and moves below the belly button to the lower right side.
• Pain that does not go away and gets worse when the person moves, walks, or coughs.
• Pain in any part of the belly or on the side.
• Nausea, throwing up, and not wanting to eat.
• Constipation, back pain, and a slight fever.
• A general feeling of being sick, and a pain that is hard to describe.

If the inflamed appendix is not surgically removed and the infection gets worse, the wall of the appendix can break open (rupture). This spreads infection into the belly area, causing peritonitis. Peritonitis is a serious condition that, in rare cases, can lead to death.