If appendicitis is not treated, the appendix can burst and cause potentially life-threatening infections.

Call 999 to ask for an ambulance if you have abdominal pain that suddenly gets much worse and spreads across your abdomen.

These are signs your appendix may have burst.


If your appendix bursts, the lining of your abdomen (peritoneum) will become infected with bacteria. This is called peritonitis.

It can also damage your internal organs.

Symptoms of peritonitis can include:

If peritonitis is not treated immediately, it can cause long-term problems and may even be fatal.

Treatment for peritonitis usually involves antibiotics and surgery to remove the appendix.


Sometimes an abscess forms around a burst appendix. This is a painful collection of pus that forms when the body tries to fight the infection. 

In rare cases an abscess can form as a complication of surgery to remove the appendix.

Abscesses can sometimes be treated using antibiotics, but in most cases the pus needs to be drained from the abscess.

This can be carried out under ultrasound or CT guidance. You'll be given a local anaesthetic and a needle will be inserted through your skin, followed by the placement of a drain.

If an abscess is found during surgery, the area is carefully washed out and a course of antibiotics is given.

Find out more about treating abscesses

Page last reviewed: 21 October 2022
Next review due: 21 October 2025