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 poo forms.

Nobody knows exactly what the appendix does, but removing it isn't harmful.

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 the lower right-hand side, where the appendix usually lies, and becomes constant and severe.

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

You may lose your appetite, feel sick and have constipation or diarrhoea.

Read more information about the symptoms of appendicitis.

When to get medical help

If you have abdominal pain that's gradually getting worse, contact your GP or 111 immediately.

Call 999 to ask for an ambulance if you have pain that suddenly gets worse and spreads across your abdomen, or if your pain temporarily improves before getting worse again.

If your pain eases for a while but then gets worse, your appendix may have burst, which can lead to life-threatening complications.

How appendicitis is treated

If you have appendicitis, it's likely your appendix will need to be 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.

It's most commonly carried out as keyhole surgery (laparoscopy).

Several small cuts are made in the abdomen, allowing special surgical instruments to be inserted.

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

It usually takes a couple of weeks to make a full recovery after your appendix has been removed.

But strenuous activities may need to be avoided for up to six weeks after having open surgery.

Read more information about treating appendicitis.

What causes appendicitis?

It's not clear what causes appendicitis. In most cases it may be that something blocks the entrance of the appendix.

For example, it could become blocked by a small piece of poo or an upper respiratory tract infection could cause the lymph node within the wall of the bowel to become swollen.

If the obstruction causes inflammation and swelling, it could lead to increased pressure within the appendix, which may then burst.

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

Who's affected?

Appendicitis is a common condition. It's estimated around 1 in every 13 people develop it at some point in their life.

You can get appendicitis at any age, but it usually affects young people aged between 10 and 20 years.


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

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

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

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

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

When to get medical help

If you have abdominal pain that's gradually getting worse, contact your GP or local out-of-hours service immediately.

If these options aren't available, call 111.

Appendicitis can easily be confused with something else, such as

In women, symptoms similar to those of appendicitis can sometimes have a gynaecological cause, such as an ectopic pregnancy, menstrual pain or pelvic inflammatory disease (PID)..

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

Call 999 for an ambulance if you have pain that suddenly gets worse and spreads across your abdomen, or if your pain temporarily improves before getting worse again.

If your pain eases for a while but then gets worse, your appendix may have burst.

A burst appendix can cause peritonitis, which is a serious infection of the inner lining of the abdomen.

Read more information about the complications of 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:

  • gastroenteritis
  • severe irritable bowel syndrome (IBS)
  • constipation
  • a bladder or urine infection

Your GP will ask about your symptoms, examine your abdomen, and see if the pain gets worse when they press on the area around your appendix (the lower right-hand side of your abdomen).

If you have the typical symptoms of appendicitis, your GP will usually be able to make a confident diagnosis.

In this case, you'll immediately be referred to hospital for treatment.

Further tests

If your symptoms are not typical, further tests may be required to confirm the diagnosis and rule out other conditions.

You may have:

It can sometimes take time to get test results.

Your surgeon may recommend a laparoscopy to examine your appendix and pelvic organs if the diagnosis is still uncertain.

Removing the appendix is usually recommended if appendicitis is suspected, rather than risk it bursting.

This means some people will have their appendix removed even though it's eventually found to be normal.

If a doctor is unsure whether you have appendicitis, they may recommend waiting up to 24 hours to see if your symptoms improve, stay the same,or get worse.

If they suspect that your appendix has burst, you will be sent to hospital immediately for treatment.


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

Surgery is often 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 risk it bursting.

In humans, the appendix does not perform any important function and removing it does not cause any long-term problems.

Appendicectomy (appendectomy)

Removal of the appendix is carried out under general anaesthetic, using either keyhole or open surgery.

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 three or four small cuts (incisions) in your tummy (abdomen).

Special instruments are 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 with a light and a camera, which relays images of the inside of the abdomen to a television monitor
  • small surgical tools used to remove the appendix

After your appendix has been removed, dissolvable stitches may be used to close the incisions.

If regular stitches are used, they'll need to be removed at your GP surgery 7-10 days later.

Open surgery

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

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

In open surgery, a single larger cut is made in the lower right-hand side of the abdomen to remove the appendix.

When there's widespread infection of the inner lining of the abdomen (peritonitis), it is sometimes necessary to operate through a cut along the middle of the abdomen. This procedure is 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 sent to a laboratory to check for signs of cancer.

This is a precautionary measure and 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 procedure is carried out promptly, you may be able to 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 it's likely you'll have some pain and bruising. This improves over time, but you can take painkillers if necessary.

If you have had keyhole surgery, you may have 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 have constipation for a short period after the operation.

To help reduce this, do not take codeine painkillers, eat plenty of fibre and drink plenty of fluids.

Your GP can prescribe medication if the problem is particularly troublesome.

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

Your should be able to return to normal activities in a couple of weeks, although you may need to avoid more strenuous activities for four to six weeks after open surgery.

Your surgeon should discuss this with you.

When to get medical advice

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

Contact your care team at the hospital or your GP if you:

  • have increased pain and swelling
  • start vomiting repeatedly
  • have a high temperature
  • have discharge coming from the wound
  • notice the wound is hot to touch

These symptoms could be a sign of infection.


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

But like all types of surgery, there are some risks, including:

  • wound infection - although 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 are 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 keyhole surgery.

The use of general anaesthetic also carries some risks, such as the risk of an allergic reaction or inhaling stomach contents, leading to pneumonia.

But serious complications like this are very rare.

Alternatives to emergency surgery

In some cases, appendicitis can cause a lump called an appendix mass to form on the appendix.

The lump is made up of appendix and fatty tissue, and is the body's way of trying to deal with the problem and heal itself.

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

Instead, you will be given a course of antibiotics and an appointment to have an operation a few weeks later, when the mass has settled.

There's not enough clear evidence to suggest that antibiotics could be used to treat appendicitis as an alternative to surgery.


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

Call 999 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:

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

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 (about 1 in 500) 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 computerised tomography (CT) guidance. You'll be given a local anaesthetic and a needle will be inserted through the skin, followed by placement of a drain.

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

The information on this page has been adapted by NHS Wales from original content supplied by NHS UK NHS website
Last Updated: 29/01/2024 07:50:17