Appendicitis is inflammation of the appendix, a small pouch attached to the large intestine. It needs prompt medical assessment because an untreated appendix can rupture and cause a serious infection inside the abdomen.
Symptoms
Pain often begins near the belly button and then moves toward the lower right side of the abdomen, where it may become more constant and severe. Movement, coughing or pressure can make the pain worse.
Other symptoms may include:
- Loss of appetite
- Nausea or vomiting
- Fever
- Abdominal swelling
- Constipation or diarrhea
- Difficulty passing gas
Not everyone develops the typical pattern. Symptoms can be different in young children, older adults and during pregnancy. Urinary, intestinal and gynecologic conditions can cause similar abdominal pain.
Diagnosis
A healthcare professional will review the symptoms and examine the abdomen. Blood tests can look for signs of infection or inflammation, and urine testing can help identify urinary causes of pain. Pregnancy testing may be appropriate.
Ultrasound, CT or MRI may be used when imaging is needed. There is no single test that identifies every case, so observation and repeat examination may sometimes be necessary.
Treatment
Treatment commonly includes antibiotics and surgery to remove the appendix, called an appendectomy. Minimally invasive surgery is frequently used. In selected uncomplicated cases, antibiotics without immediate surgery may be considered after specialist assessment, although appendicitis can recur.
If the appendix ruptures, complications such as peritonitis or an abscess can develop. Treatment may require surgery, drainage, intravenous antibiotics and fluids.
When to seek urgent care
Seek urgent medical assessment for abdominal pain that is steadily worsening, moves toward the lower right abdomen, or occurs with fever, repeated vomiting or significant abdominal tenderness. Do not delay medical care to see whether severe or worsening pain resolves on its own.
Use your local emergency medical service for severe or widespread abdominal pain, a rigid or extremely tender abdomen, collapse, confusion, breathing difficulty or other signs of a medical emergency.
Related topics
Sources
Last reviewed: 4 September 2026
Medical disclaimer: This information is general and does not replace individual medical assessment, diagnosis or treatment.