Appendicitis is a painful swelling of the appendix, a finger-like pouch connected to the large intestine.

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 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.

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  111 for advice.

You should call 999 for an ambulance if you have pain that suddenly becomes and continues to get worse and spreads across your abdomen. These are signs that your appendix may have burst, which can lead to potentially life-threatening complications.

How appendicitis is treated

In most cases of appendicitis, the appendix will need 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 single larger 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 six weeks after open surgery. 

What causes appendicitis?

It's not exactly clear what the causes of appendicitis are, although most cases are thought to occur when something, usually a small piece of faeces (stool) or a swollen lymph node within the wall of the bowel (often following an upper respiratory tract infection), blocks the entrance of the appendix.

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 are not fully understood, there's no guaranteed way of preventing appendicitis.

Who is affected

Appendicitis is a common condition. Around 40,000 people are admitted to hospital with appendicitis each year in England and it's estimated that around one in every 13 people will develop it at some point in their life.

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

What is the appendix?

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

No one knows exactly why we have an appendix. Removing it is not harmful.

Symptoms of appendicitis 

Appendicitis typically starts with a pain in the middle of your abdomen (tummy) 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


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  111 for advice.

Appendicitis can easily be confused with something else, such as agastroenteritis, severe irritable bowel syndrome (IBS), constipation, bladder or urine infections and occasionally Crohn's disease. 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 that your appendix may have burst.

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


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 appendix may be located in a slightly different part of their body, such as the pelvis, behind the large intestine or behind the liver.

Some people develop pain similar to appendicitis, but it's caused by something else, such as a bladder or urine infection, Crohn's diseaseor gastroenteritis.

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 which case you will be referred immediately to hospital for treatment.

Further tests

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

Further tests may involve: 

a blood test to look for signs of infection

a urine test to rule out other conditions, such as a bladder infection

a computerised tomography (CT) scan or an ultrasound scan to see if the appendix is swollen

a pregnancy test for women

It can sometimes take several days to get test results. Therefore it is likely you will be advised to have your appendix removed if appendicitis is suspected, rather than run the risk of it bursting. This means that some people will have their appendix removed even though it is 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 that your appendix has burst, you will be sent to hospital immediately for treatment.

Treating appendicitis 

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

Surgery will also usually be recommended if there is a chance you have appendicitis but it has not been possible to make a clear diagnosis. This is because it is considered safer to remove the appendix than run the risk of the appendix bursting.

In humans, the appendix does not perform any important function and having it removed does not 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 three or four small cuts in your abdomen (tummy). Special instruments are then inserted, including:

a tube through which gas is pumped 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 be closed with stitches that either dissolve over the next few days or need to be removed during an appointment at your GP surgery 7-10 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 is not very experienced in laparoscopic removal

people who have previously had open abdominal surgery

In these cases, the operation will involve making a single larger cut in the lower right hand side of your abdomen to remove the appendix. When there is widespread peritonitis (infection of the inner lining of the abdomen) it is sometimes necessary to operate through a long cut along the middle of the abdomen (a laparotomy).

As with keyhole surgery, the incision will be closed with stitches that either dissolve over the next few days or need to be removed at a later date. 

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


One of the main advantages of keyhole surgery is that 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 then most patients can go home within 24hrs.

With open or complicated surgery (for example, if you have peritonitis), it may be a week before you're well enough to go home.

For the first few days after the operation you are likely to experience some pain and bruising. This will improve 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 by staying well hydrated, although 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. In most cases, you can return to normal activities in a couple of weeks, although more strenuous activities may need to be avoided for four to six 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:

wound infection (although antibiotics may be given before, during or after the operation to minimise the risk of serious infections)

bleeding under the skin causing a firm swelling (haematoma)– this will usually get 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 the laparoscopic approach.

The use of general anaesthetic also carries some risks, such as the risk of an allergic reaction or inhaling any stomach content leading topneumonia. However, serious complications such as 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 is not necessary to operate immediately. Instead, you will 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 is not enough clear evidence to suggest this is the case.

Complications of appendicitis 

If appendicitis is not 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 that 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

being sick

a high temperature (fever)

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 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 will need 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 placement of a drain.

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