Appendicitis
Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.
Source: MedlinePlus, National Library of Medicine. Read the original source
MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.
The appendix is a small, tube-like organ attached to the first part of the large intestine. It is located in the lower right part of the abdomen. It has no known function. A blockage inside of the appendix causes appendicitis. The blockage leads to increased pressure, problems with blood flow, and inflammation. If the blockage is not treated, the appendix can burst and spread infection into the abdomen. This causes a condition called peritonitis.
The main symptom is pain in the abdomen, often on the right side. It is usually sudden and gets worse over time. Other symptoms may include:
- Swelling in the abdomen
- Loss of appetite
- Nausea and vomiting
- Constipation or diarrhea
- Inability to pass gas
- Low fever
Not everyone with appendicitis has all these symptoms.
Appendicitis is a medical emergency. Treatment almost always involves removing the appendix. Anyone can get appendicitis, but it is more common among people 10 to 30 years old.
NIH: National Institute of Diabetes and Digestive and Kidney Diseases
Symptoms, tests and care options
Further reading selected by MedlinePlus. Links open the original organizations’ websites.
- Abdominal and Pelvic CT · Radiological Society of North America
- Abdominal exploration - series · Medical Encyclopedia
- Abdominal Pain (Stomach Pain), Short-Term · American Academy of Family Physicians
- Appendectomy - series · Medical Encyclopedia
- Treating Appendicitis: Comparing Surgery with Antibiotic Treatment · Nemours Foundation
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For a life-threatening emergency, call 911 in the U.S. or your local emergency number.
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