Appendicitis is inflammation of the appendix. The appendix is a small, tube-like organ that hangs from the large intestine. It appears to have no clear function.


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Appendicitis usually occurs when the appendix becomes inflamed. This can be caused by something trapped in the appendix, such as:

  • A piece of dried stool
  • A piece of food
  • Tumors
  • Scar tissue
  • Worms
  • Barium after a diagnostic exam
  • Overgrowth of the lymph tissue of the appendix

The lining of the appendix continues to produce mucus, but it has no place to go. Bacteria normally found in the intestines multiply and make toxins in the lining of the appendix. Pressure builds and causes severe pain in the abdomen. The wall of the appendix can break open. If the appendix ruptures, its contents can spill into the abdominal cavity. This causes serious inflammation in the abdominal cavity called peritonitis]]> , which can be fatal.


Risk Factors

These factors increase your chance of developing appendicitis:

  • Sex: male
  • Age: teen years
  • Family members who have had appendicitis


Symptoms usually come on suddenly. Pain generally increases during a 6- to 12-hour period. Patients may experience some or all of the following symptoms:

  • Pain
    • Starts as discomfort around the belly button
    • Usually moves to the right side of the abdomen over several hours
    • May be in a different location if the appendix is not in the usual place
    • Increases as inflammation in the appendix builds
    • Worsens with sneezing, coughing, and deep breathing
    • May increase with movement
  • Loss of appetite
  • Nausea
  • Vomiting
  • Swelling of the abdomen
  • Abdomen feels hard and is sensitive to touch
  • Constipation]]>
  • Mild ]]>diarrhea]]>
  • Slight fever

If the appendix ruptures, symptoms include:

  • Pain becoming stronger and spreading across the abdomen
  • Increasing fever

Note: Symptoms may be atypical in infants, children, pregnant women, and the elderly.



Seek immediate medical care if you have severe pain in the abdomen. Appendicitis can be hard to diagnose. Symptoms vary and can be similar to symptoms of other diseases.

The doctor will ask about your symptoms and medical history, and perform a physical exam. The exam will include:

  • A careful examination of the abdomen
  • A rectal exam

Other tests to determine the cause of your pain may include:

  • Blood tests—to see if you have an infection
  • Urine tests—to rule out urinary tract infection]]>
  • ]]>CT scan]]> or ]]>ultrasound]]> —These tests, which are only helpful in cases of late appendicitis, are used to look for signs of an inflamed appendix or abscess that may be causing the pain.
  • ]]>Laparoscopy]]> —A thin, lighted tube is inserted through a small incision near the belly button.



Appendicitis is treated by surgically removing the appendix as soon as possible. If the diagnosis is not certain, the doctor will carefully monitor your condition for 6-12 hours before operating. You will also be given antibiotics to fight infection.

Researchers are studying to see if surgery can be avoided in certain cases. For example, in a study, patients were treated with intravenous antibiotics and observed, rather than having surgery right away. ]]>

If you are diagnosed with appendicitis, follow your doctor's instructions.


There are no guidelines for preventing appendicitis because it comes on suddenly and the cause is usually unknown. To decrease the risk of rupture, get medical care right away for severe abdominal pain.