About appendicitis

Appendicitis is a painful swelling of the appendix. The appendix is a small, thin pouch about 5-10cm (2-4 inches) long. It's connected to the large intestine, where stools (faeces) are formed.

Nobody knows exactly why we have an appendix, but removing it isn't harmful.

Appendicitis typically starts with a pain in the middle of your tummy (abdomen) that may come and go.

Within hours, the pain travels to the lower right-hand side, where the appendix usually lies, and becomes constant and severe.

Pressing on this area, coughing, or walking may all make the pain worse. You may lose your appetite, feel sick, and occasionally experience diarrhoea.

Read more about the symptoms of appendicitis.

When to get medical help

If you're experiencing abdominal pain that's gradually getting worse, contact your GP or local out-of-hours service immediately. If these options aren't available, call NHS 24 111 Service for advice.

You should call 999 for an ambulance if you have sudden pain that continues to get worse and spreads across your abdomen.

These are signs your appendix may have burst, which can lead to potentially life-threatening complications.

Read more about: 

diagnosing appendicitis 

complications of appendicitis

How appendicitis is treated

In most cases of appendicitis, the appendix needs to be surgically removed as soon as possible.

Removal of the appendix, known as an appendectomy or appendicectomy, is one of the most common operations in the UK and its success rate is excellent.

The operation is most commonly performed as keyhole surgery (laparoscopy), which involves making several small cuts in your abdomen, through which special surgical instruments are inserted.

Open surgery, where a larger, single cut is made in the abdomen, is usually carried out if the appendix has burst or access is more difficult.

Most people make a full recovery from an appendectomy in a couple of weeks, although strenuous activities may need to be avoided for up to 6 weeks after open surgery. 

Read more about treating appendicitis.

What causes appendicitis?

It's not exactly clear what the causes of appendicitis are. Most cases are thought to occur when something blocks the entrance of the appendix.

For example, a blockage may be formed by a small piece of faeces or an upper respiratory tract infection could lead to a swollen lymph node within the wall of the bowel.

This obstruction leads to the development of inflammation and swelling. The pressure caused by the swelling can then lead to the appendix bursting.

As the causes aren't fully understood, there's no guaranteed way of preventing appendicitis.

Who's affected?

Appendicitis is a common condition. Around 40,000 people are admitted to hospital with appendicitis each year in England.

It's estimated around 1 in every 13 people develop it at some point in their life.

Appendicitis can develop at any age, but it's most common in young people aged from 10 to 20 years old.

Symptoms of appendicitis

Appendicitis typically starts with a pain in the middle of your tummy (abdomen) that may come and go.

Within hours, the pain travels to your lower right-hand side, where the appendix is usually located, and becomes constant and severe.

Pressing on this area, coughing, or walking may all make the pain worse.

If you have appendicitis, you may also have other symptoms, including:

  • feeling sick (nausea)
  • being sick
  • loss of appetite
  • diarrhoea
  • a high temperature (fever) and a flushed face

When to get medical help

If you're experiencing abdominal pain that's gradually getting worse, contact your GP or local out-of-hours service immediately. If these options aren't available, call NHS 24 111 Service for advice.

Appendicitis can easily be confused with something else, such as:

In young women, these symptoms can sometimes have a gynaecological cause, such as an ectopic pregnancy or menstrual pain.

However, any condition that causes constant stomach pain requires urgent medical attention.

You should call 999 for an ambulance if you get a pain that suddenly becomes worse and spreads across your abdomen. These are signs your appendix may have burst.

If the appendix bursts, it can cause peritonitis, a potentially serious infection of the inner lining of the abdomen.

Read more about the complications of appendicitis.

Diagnosing appendicitis

Appendicitis can be tricky to diagnose unless you have the typical symptoms, which are only present in about half of all cases.

Also, some people's appendixes may be located in a slightly different part of their body, such as:

  • the pelvis
  • behind the large intestine
  • around the small bowel
  • near the right lower part of the liver

Some people develop pain similar to appendicitis, but it's caused by something else, such as:

Your GP will ask about your symptoms, examine your abdomen, and see if the pain gets worse when pressure is applied to the appendix area (your lower right-hand side).

If your symptoms are typical of appendicitis, this is normally enough for your GP to make a confident diagnosis. In this case, you'll immediately be referred to hospital for treatment.

Further tests

If your symptoms aren't typical, further tests may be required in hospital to confirm the diagnosis and rule out other conditions.

Further tests may involve: 

It can sometimes take time to get test results. Your surgeon may recommend a laparoscopy to inspect your appendix and pelvic organs if the diagnosis is still uncertain.

You'll usually be advised to have your appendix removed if appendicitis is suspected, rather than run the risk of it bursting. This means some people will have their appendix removed even though it's eventually found to be normal.

In some cases where a diagnosis is not certain, a doctor may recommend waiting up to 24 hours to see if your symptoms improve, stay the same, or get worse.

If your doctor suspects your appendix has burst, you'll be sent to hospital immediately for treatment.

Read more about treating appendicitis.

Treating appendicitis

If you have appendicitis, your appendix usually needs to be removed as soon as possible. This operation is known as an appendectomy or appendicectomy.

Surgery is usually also recommended if there's a chance you have appendicitis but it's not been possible to make a clear diagnosis.

This is because it's considered safer to remove the appendix than run the risk of the appendix bursting.

In humans, the appendix doesn't perform any important function and having it removed doesn't cause any long-term problems.

The procedure

Appendectomies are carried out under general anaesthetic using either a keyhole or open technique.

Keyhole surgery

Keyhole surgery (laparoscopy) is usually the preferred method of removing the appendix because the recovery tends to be quicker than with open surgery.

This operation involves making 3 or 4 small cuts (incisions) in your tummy (abdomen). Special instruments are then inserted, including:

  • a tube that gas is pumped through to inflate your abdomen – this allows the surgeon to see your appendix more clearly and gives them more room to work
  • a laparoscope – a small tube containing a light source and a camera, which relays images of the inside of the abdomen to a television monitor
  • small surgical tools used to remove the appendix

Once the appendix has been removed, the incisions will usually be closed with dissolvable stitches. Regular stitches may also be used, which need to be removed at your GP surgery 7 to 10 days later.

Open surgery

In some circumstances, keyhole surgery isn't recommended and open surgery is performed instead. These include:

  • when the appendix has already burst and formed a lump called an appendix mass
  • when the surgeon isn't very experienced in laparoscopic removal
  • people who have previously had open abdominal surgery

In these cases, the operation involves making a single larger cut in the lower right-hand side of your abdomen to remove the appendix.

When there's widespread peritonitis – infection of the inner lining of the abdomen – it's sometimes necessary to operate through a long cut along the middle of the abdomen in a procedure called a laparotomy.

As with keyhole surgery, the incision is closed using either dissolvable stitches or regular stitches that need to be removed at a later date. 

After both types of surgery, the removed appendix is routinely sent to a laboratory to check there are no signs of cancer. This is a precautionary measure, although it's rare for a serious problem to be found.


One of the main advantages of keyhole surgery is the recovery time tends to be short and most people can leave hospital a few days after the operation.

If the appendix is operated upon promptly, most patients can go home within 24 hours. With open or complicated surgery – for example, if you have peritonitis – it may take up to a week before you're well enough to go home.

For the first few days after the operation you're likely to experience some pain and bruising. This improves over time, but you can take painkillers if necessary.

If you had keyhole surgery, you may experience pain in the tip of your shoulder for about a week. This is caused by the gas that was pumped into the abdomen during the operation.

You may also experience some short-term constipation. You can help reduce this by not taking codeine painkillers, eating plenty of fibre, and staying well hydrated. Your GP can prescribe medication if the problem is particularly troublesome.

Before leaving hospital, you'll be advised about caring for your wound and what activities you should avoid.

In most cases, you can return to normal activities in a couple of weeks, although more strenuous activities may need to be avoided for 4 to 6 weeks after open surgery.

When to seek medical advice

While you recover, it's important to keep an eye out for signs of any problems.

Contact the hospital unit where the appendectomy was performed or your GP for advice if you notice:

  • increasing pain and swelling
  • you start vomiting repeatedly
  • a high temperature (fever)
  • any discharge coming from the wound
  • the wound is hot to touch

These symptoms could be a sign of infection.


Appendectomies are one of the most commonly performed operations in the UK, and serious or long-term complications are rare.

However, like all types of surgery, there are some risks. These include:

  • antibiotics may be given before, during, or after the operation to minimise the risk of serious infections
  • bleeding under the skin that causes a firm swelling (haematoma) – this usually gets better on its own, but you should see your GP if you're concerned
  • scarring – both surgical techniques will leave some scarring where the incisions were made
  • a collection of pus (abscess) – in rare cases, an infection caused by the appendix bursting can lead to an abscess after surgery
  • hernia – at the site of the open incision or any of the incisions used in the laparoscopic approach

The use of general anaesthetic also carries some risks, such as the risk of an allergic reaction or inhaling stomach contents, leading to pneumonia. However, serious complications like this are very rare.

Alternatives to emergency surgery

In some cases, appendicitis can lead to the development of a lump on the appendix called an appendix mass.

This lump, consisting of appendix and fatty tissue, is an attempt by the body to deal with the problem and heal itself.

If an appendix mass is found during an examination, your doctors may decide it's not necessary to operate immediately.

Instead, you'll be given a course of antibiotics and an appointment will be made for an appendectomy a few weeks later, when the mass has settled.

Another possible alternative to immediate surgery is the use of antibiotics to treat appendicitis.

However, studies have looked into whether antibiotics could be an alternative to surgery and as yet there isn't enough clear evidence to suggest this is the case.

Complications of appendicitis

If appendicitis isn't treated, the appendix can burst and cause potentially life-threatening infections.

Call 999 for an ambulance if you have abdominal (tummy) pain that suddenly gets much worse and spreads across your abdomen. These are signs your appendix may have burst.


If your appendix bursts, it releases bacteria into other parts of the body. This can cause a condition called peritonitis if the infection spreads to the peritoneum, the thin layer of tissue that lines the inside of the abdomen.

Symptoms of peritonitis can include:

  • severe continuous abdominal pain
  • feeling sick or being sick
  • a high temperature (fever)
  • a rapid heartbeat
  • shortness of breath with rapid breathing
  • swelling of the abdomen

If peritonitis isn't treated immediately, it can cause long-term problems and may even be fatal. Treatment for peritonitis usually involves antibiotics and the surgical removal of the appendix (appendectomy).


Sometimes an abscess forms around a burst appendix. This is a painful collection of pus that occurs as a result of the body's attempt to fight the infection. 

It can also occur as a complication of surgery to remove the appendix in about 1 in 500 cases.

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

This can be carried out under ultrasound or computerised tomography (CT) guidance using local anaesthetic and a needle inserted through the 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.

Last updated:
29 May 2023