An endoscopy procedure is also called a gastroscopy. This is a test using a thin flexible tube called an endoscope.

Endoscopy procedure

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If you are looking for a private gastroenterology / endoscopy test in London, we would be delighted to help you. Our consultant gastroenterologists offer the highest quality investigations in some of London’s very best private hospitals.

What is endoscopy procedure?

An endoscopy procedure is also called a gastroscopy. This is a test using a thin flexible tube called an endoscope, to examine the inner lining of the oesophagus (gullet), stomach and upper small bowel (duodenum).

Private Endoscopy London

The procedure is usually done to make a diagnosis, but treatments can be also be carried out. The doctor will tell you whether you are having the gastroscopy for diagnosis or treatment before starting.

Sedation Options for Your Endoscopy

Endoscopy is a simple procedure that can be carried out while you’re awake. If you are having a private endoscopy in London, you may be able to choose whether to remain fully awake or have a sedative to help you relax. You should consider the options carefully and discuss them with your doctor before the procedure.

Endoscopy without a sedative

It isn’t always necessary to have a sedative, so you may decide to remain awake when you have a private endoscopy at the London clinic. If you are having the procedure without a sedative:

An anaesthetic spray will be used on the back of your throat. It will make the back of your throat feel numb and prevent you from feeling any pain. The spray should help you to swallow the endoscope more easily. You will be asked to lie down on your side.

The endoscope will then be passed into your mouth and down your throat. You will feel this happening, but it shouldn’t be painful. The doctor will ask you to swallow as the tube moves down your throat.

Once the investigation is complete, the endoscope will be removed. Your throat will feel numb and you should avoid eating or drinking anything for about an hour until the anaesthetic wears off.

Having a sedative

If you feel uncomfortable having the procedure while you are fully aware or your doctor recommends it, you may be given a sedative before your private endoscopy. The sedative is a drug that will help you to feel sleepy and relaxed during the procedure.

You will be given an injection of sedative before the endoscopy begins. It will take a few minutes for the drug to start working. The sedative will make you feel drowsy and less aware of what is happening, but you will still be awake during the procedure.

When the endoscopy is over, you will rest for a while as the sedative wears off. You should arrange for someone to pick you up and take it easy for the rest of the day. Your memories of the procedure may be a bit hazy afterwards.

Preparing for Procedure

Preparation is straightforward. Please do not eat for 6 hours before the test. You can continue to drink clear fluids until 4 hours before the gastroscopy.

You will need to arrive at the hospital at least 30 minutes before the test is done. This gives time to complete the registration forms with the nurses and to have your vital signs such as pulse and blood pressure checked.

Routine pre-procedure checks are done to ensure that it is safe for you to have the test.

Diabetics and patients on blood thinning medicines

Special preparations are needed for patients with diabetes, particularly those who take diabetes medicine as well as for patients on blood thinning medicines. Please discuss these with our doctors who will advise you how to prepare.

Arriving at the Hospital

When you arrive at the hospital, you will come to the endoscopy unit. You will be shown to your cubicle where you will meet the nurse who will look after you during your stay. She will also verify your personal details and preferred method of payment.

The nurse will then prepare you for your procedures. If you have any worries or questions at this stage don’t be afraid to ask.

The staff will want you to be as relaxed and informed as possible for the test and will be happy to answer your queries.

The procedure will happen about half an hour after you arrive.

Your doctor will explain the test to you and will ask you to sign a consent form. This is to signify that you understand the test and its implications.

Please tell the consultant or nurse if you have had any allergies or bad reactions to drugs or other tests.

During the Procedure

When you go into the endoscopy room you will be asked to remove any false teeth and lie on your left side on a trolley. You will have some equipment attached to you so we can monitor you blood pressure and your oxygen levels.

You will also have a small amount of oxygen during the procedure.

A plastic mouthpiece will be placed between your teeth to help keep your mouth slightly open.

Most people prefer to be sedated (sleepy) for the tests. The doctor will administer the medication (painkillers and sedation) via a small plastic tube placed in the back of your hand or arm.

The medication may take a few minutes to work. The medication makes you relaxed and drowsy; it is not a general anaesthetic. The doctor will then start the gastroscopy by gently passing the gastroscope (endoscope) through your mouth into your stomach.

The gastroscopy usually takes around 10 minutes unless treatment is being performed. If you get a lot of saliva in your mouth, the nurse will suck this out with a sucker.

Sometimes the doctor takes a biopsy (a sample of the bowel lining). A small piece of tissue is removed painlessly through the working channel of the endoscope, using tiny forceps. This is then sent to the laboratory for further tests.

Does it hurt?

The test should not be painful but it may feel uncomfortable in the throat. You may develop a sore throat for 2 – 3 days after the procedure.

After the procedure

After the gastroscopy procedure is complete, you will return to your cubicle. You will stay there for approximately one hour so the effects of the sedation can wear off. Your blood pressure and oxygen levels will be monitored during this time.

If you do not have sedation you will not need to stay in recovery for as long. You will also be offered a drink and some biscuits. You may bring your own food if you prefer. One of the doctors or nurses will come to explain the results of your gastroscopy. You should expect to stay in the hospital for a total of 2 or 3 hours.

Going home

If you have had sedation for your endoscopy procedure, do not use public transport, particularly if you will need to stand on the train or bus.

  • Do not drive yourself. Please have someone to take you home in a car or taxi
  • Do not drink alcohol for 24 hours after sedation is given
  • Do not drive a car or operate heavy machinery until the day after sedation is given

At home

Once you get home you may eat and drink as normal.

You may find that you have a sore throat. You may also feel a bit full up or bloated. This is because of the air in your bowel. This feeling usually only lasts for a few hours but may last for a few days in some people. Peppermint or chamomile tea helps to release the trapped wind.


Gastroscopy is a common test with very few side effects or complications. However you should be aware of the following potential complications:

Overall, the risks of haemorrhage (bleeding) or perforation (a hole in the lining of the bowel) are very low at about 1 in 15,000 (British Society of Gastroenterology). If treatment is carried out, the risks are higher but are still low. The doctor will give you specific information about the risks in your case.

Sedation causes breathing problems in about 1 in 200 cases although these are usually mild (British Society of Gastroenterology). You will be monitored through out the procedure and the sedation can be reversed if necessary.

What are the alternatives?

Barium Swallow or Barium Meal: These are X-ray tests. They are not as accurate as gastroscopy for most conditions although for a small number of people with swallowing problems, a barium swallow can be useful.

Abdominal Ultrasound: This test is useful for detecting gallstones and abnormalities in the liver and kidneys. It cannot easily examine the stomach, however.

Manometry and pH studies: These tests are sometimes very helpful for patients with swallowing difficulties and may be used in addition to gastroscopy.

Abdominal CT scan: This test can examine the entire abdomen. It involves X-rays, however, and no biopsy samples, so it is generally used as a follow up test, for example to determine the size of a growth seen during gastroscopy.

Endoscopy Procedure Findings

If you are wondering whether you should have an endoscopy test, it is worth being aware of what the doctors look for.

Our private gastroenterologists are all experts in this field and have many years of experience. They also do these tests all the time, so they are used to looking for even subtle abnormalities.

Major endoscopy findings

Findings at an endoscopy procedure vary widely. In most people the test is entirely normal. Below, we list the commonest abnormal endoscopic findings.

  • Gastroesophageal reflux disease (oesophagitis and hiatus hernias)
  • Barrett’s oesophagus
  • Stomach ulcers
  • Gastritis
  • Helicobacter pylori infection
  • Stomach cancer
  • Coeliac disease

Gastroesophageal Reflux

Inflammation of the lower part of the oesophagus causes heartburn and a feeling of fullness or difficulty swallowing. This can be treated by diet and medicines to prevent production of stomach acid.

Reflux may cause other problems such as a stricture or narrowing of the oesophagus.

Barrett’s Oesophagus

This is also a complication of acid reflux. The lining of the oesophagus is normally pinklike the lining of the mouth. In this condition, it changes from the normal pinkcolour to a salmon red colour, more like the lining of the stomach. Barrett’s oesophagus is important because in a small number of people, it predisposes to oesophageal cancer.

Stomach Ulcers

Ulcers commonly occur in the duodenum, the first part of the small bowel. They may also occur in the stomach itself. Ulcers usually heal very easily by simply reducing the amount of stomach acid. A repeat endoscopy is often recommended for people with stomach ulcers but not duodenal ulcers.

Signs of stomach ulcers

An ulcer is an area where the lining of the stomach has eroded away. The area may look red and inflamed, or white with a slough lining the eroded area. Another sign of stomach ulcers is visible blood vessels in the base of the ulcer and occasionally, blood is seen as the ulcer is actively bleeding. Both of these findings may require specialist endoscopic treatment.

Stomach ulcers may occur either singly, or as a group. If the doctor sees multiple small ulcers, particularly in the lower part of the stomach (antrum), the cause is usually aspirin or another non-steroidal anti-inflammatory drug such as ibuprofen. Stopping the offending drug will heal the ulcers in a very short time. Some people cannot stop these drugs. Taking a proton pump inhibitor may also help heal the ulcers.

Other Stomach Ulcer Causes

In the UK, twenty years ago, most ulcers were caused by Helicobacter pylori. This is much less common now than it used to be. Find out more here. If H.pylori is present, it can usually be treated with antibiotics.


Inflammation of the stomach is commonly reported. This should be interpreted with care. The stomach is a dangerous place with acid and foreign bugs ingested in food. Gastritis may actually be a normal state for many people and may not be causing symptoms.

Helicobacter pylori infection

H. pylori is a bacteria which lives almost exclusively in the stomachs of human beings. In most people it causes no problems at all, but in some people, it causes symptoms, ulcers or even cancer. Read more here

Stomach Cancer

Thankfully, this is rare. Endoscopy is the best test for stomach cancer as a tissue sample can be taken to make the diagnosis. The small sample is sent to the laboratory for analysis by one of our specialist histopathologists.

Coeliac Disease

Coeliac disease affects almost 1 in 100 people in the UK. It is common and important because of the risks that untreated disease cause. These include diarrhea and bloating but also important problems such as thinning of the bones (osteoporosis) and rare problems including stomach cancer and small bowel lymphoma. Diagnosis relies on duodenal biopsy (a small sample of the lining of the small bowel). This can only be achieved reliably at endoscopy.

In summary

Findings at an endoscopy procedure can be varied. The doctor needs to be highly trained and skilled to detect them and to recognise different endoscopy findings, such as signs of a stomach ulcer, hiatus hernia or even stomach cancer. The doctor also needs to understand the stomach ulcer causes or, indeed, the cause of any other abnormality they see. Our top private London gastroenterologists are all experts in this area and would be happy to arrange your endoscopy test for you.

Helicobacter Pylori

One of the most common findings at endoscopy is a helicobacter pylori infection.

What is it?

Helicobacter pylori is a bug which is commonly found in the human stomach. It is not found in any other animals. It used to be very common in all humans. It was even found in Tutankhamun, the Egyptian mummy’s, stomach! It is found much less now in developed countries, although it is still common in Southern Europe, Africa and Asia.

How is it acquired?

It is believed that H. pylori is transmitted from parent to child. It only happens in close proximity, so with smaller families and larger, cleaner homes, transmission rates have fallen dramatically in the last 50 years. Helicobacter is rarely acquired in adulthood. This is important, because if it is found and successfully eradicated, it almost never returns.

What problems does it cause?

H. pylori is known to increase the risk of duodenal ulcers, stomach ulcers and stomach cancer. Until 20 years ago, almost all duodenal ulcers were caused by H. pylori. This has changed now, both because the bacteria is found far less often and also because of the increasing use of non-steroidal anti inflammatory drugs such as aspirin and ibuprofen. Ulcers are increasingly due to use of these medicines.

How is Helicobacter detected?

There are a number of ways of testing for this bacteria.

  • Blood test: this used to be used widely. It is not a good test, however. The accuracy is only around 60% and if a person has previously had eradication treatment, the blood test still remains positive for up to 5 years after the bug has been successfully treated.
  • Stool sample (Helicobacter faecal antigen): This is a simple and cheap test. It is now the test of choice for most people as it can be done at home. The only problem is that one has to collect some stool and people are not fond of doing this! This test has an accuracy of 97%.
  • Breath test: Although easy to do, this test is more expensive than the stool sample. It requires the patient to take a drink of a very slightly radioactive orange juice. A breath sample is collected 30 minutes later. If H pylori is present, the levels of radioactivity contained within the drink are detected on the breath. This test also has an accuracy of 97%.
  • Endoscopy: A small tissue sample can be taken at endoscopy and analysed for the presence of H pylori. If an endoscopy is being done anyway, this is a simple and rapid way of detecting it. With rapid test kits now available, the result is usually ready before the patient leaves the private endoscopy unit.

Why should it be eradiated?

If a person has an ulcer, removing the H. pylori will almost certainly result in permanent cure.

Many doctors eradicate this bug in the hope that it will reduce the risk of the patient getting stomach cancer. Although this seems like a good idea, there is no evidence that the strategy works!

How is it eradicated?

The bug is highly resistant to treatment. Two antibiotics and medicine to reduce stomach acid are needed for 7-14 days. Eradication rate is about 80%.

How can you check for successful eradication?

All the tests outlined above, except for the blood test, will show if the Helicobacter has been eradicated.

There is one little catch, however. A false negative test result may result in patients who are taking acid suppression medicines such as proton pump inhibitors. Test accuracy is much higher if the patient stops taking these medicines for at least a month.

What happens if it is not eradicated?

There are second line treatments for people who fail to respond to the initial antibiotic regime. However, once a person has failed to eradicate the bug with the initial treatment, further treatments are less successful.

It is possible to take special biopsy samples at endoscopy to check for sensitivity of the bug to specific antibiotics. This allows the doctor to tailor the treatment specifically to that patient.

At our private endoscopy facilities, we are able to offer this service to people who need it.

A word of caution:

It is not necessarily true that H pylori must be eradicated in everyone. This needs to be discussed on a case-by-case basis. Our highly experienced private gastroenterologists would be very happy to talk to you about your specific needs.

Booking your test

If you would like to have your endoscopy procedure performed by one of our internationally renowned private gastroenterologists in one of London’ best hospitals, please contact our office on 020 7183 7965.

We will ensure that your private gastroenterology / endoscopy appointment in London is a relaxing experience and is done by a very special doctor who will help you. We only use the latest and most modern endoscopes and have the highest quality support staff.

We are available to see patients daily for private consultations

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