What is a gastroscopy?

Gastroscopy is an examination of the inside of the gullet, stomach and the first part of your small bowel called duodenum. It is performed by using a thin, flexible fibre-optic instrument, called gastroscope that is passed through the mouth and allows the doctor to see whether there is any damage to the lining of the esophagus (gullet) or stomach, and whether there are any ulcers in the stomach or duodenum.

Your gastroenterologist or internist will decide if drug treatment alone is sufficient or whether an investigation by gastroscopy at Medicover Hospital will be necessary.

Why is a gastroscopy needed?

A screening gastroscopy is usually done to find the cause of your symptoms – such as abdominal pain, vomiting or bleeding from the digestive tract-, to make or confirm a diagnosis, help with treatment and if necessary, to decide on further investigation. Conditions sometimes can also be treated via gastroscopy, for example, polyps can be removed.

There are many reasons for this investigation including:

  • indigestion
  • anemia
  • weight loss
  • vomiting
  • passing black motions
  • vomiting blood
  • difficulty swallowing

What happens during a gastroscopy?

You will be asked to lie on the table on your left side. You are usually given a sedative and sometimes a pain-reliever medicine by injection into your vein.

The examination is prepared under sedation or general anesthesia according to your preference. The sedative will help you to relax, and, if you choose general anesthesia, put you to sleep. Generally, you will have little recollection of the procedure. In some cases, the test can be done without the sedative and you need to discuss this with the doctor before you sign the consent form.

In case of sedation the back of your throat may be sprayed with local anaesthetic to make it numb and to help you not to gag. A small mouthguard will be put between your teeth to stop you from biting the endoscope. If you have removable dental work, they will be removed before the procedure.

The endoscope will be placed into your mouth and you will be instructed to swallow it down into your stomach. The tube is just less than a centimeter in diameter and does not enter your windpipe, so there is plenty of room to breathe around it. The doctor will direct air into your stomach via the gastroscope. This will make viewing easier.

Sometimes a special instrument can be inserted through the scope, and a small sample of tissue removed (called a biopsy). This is not painful. The doctor may also take photos to refer to later. Some treatments can be performed while the endoscope is in (e.g. removing polyps, controlling blood loss from an ulcer or injecting veins — similar to varicose veins — in the stomach or esophagus).

How does a gastroscopy work?

The instrument used for this investigation is called a gastroscope. It is a flexible tube with a diameter less than that of your little finger. The gastroscope lights up the lining of your upper digestive tract and has a sensor on the end to capture video images which are relayed back to a television screen.

During the investigation, the gastroenterologist may need to take some tissue samples known as biopsies from the lining of your upper digestive tract for further analysis. This is completely painless. The samples may be retained for further tests. Photographs may be taken for your medical records.

What are the benefits and risks of gastroscopy?


  • A screening gastroscopy helps the doctor diagnose your condition accurately, so you can expect a more accurate form of treatment.
  • If the procedure is used as a treatment, such as to repair a bleeding ulcer or remove polyps, then you can expect a remarkable improvement in your condition. The procedure is painless and is usually done under light sedation.
  • In some cases, a gastroscopy can also be used to stretch or widen a narrowed portion of the esophagus.


  • Screening gastroscopy is a low-risk procedure. In fact, only 1 in every 1000 patients who undergo a gastroscopy will experience any type of complication. Very few people experience serious side effects.
  • You may have a slightly sore throat after the procedure. Air may also be trapped in your stomach causing you to feel bloated.
  • If a biopsy has been taken or treatment performed, there may be minor bleeding.
  • Very rarely, the stomach lining may be torn, and in such cases you would be admitted to hospital and an operation would be performed to repair it.
  • You may have a sore throat for 24-48 hours.  You must tell the nurse if you have any loose teeth, caps or crowns as there is a risk that they can become dislodged during the procedure.
  • Reactions to the sedative are also possible, but again rare. If you are worried about any of these risks, please speak to your doctor at Medicover Hospital before your test.

How should I prepare for a gastroscopy?

You will be asked not to eat or drink anything for at least 6 hours before the test.

If you are taking any medicines, check with your doctor if it is all right to continue taking them. You may be asked to stop taking medicines that can increase the risk of bleeding for a few days before the test; these include warfarin, aspirin and non-steroidal anti-inflammatory (NSAID) medicines. However, this depends on your individual circumstances, so you should check.

You should also inform us and your health care provider if you have any condition that requires you to take antibiotics before dental procedures — you may need antibiotics before gastroscopy too.

Before your screening gastroscopy, the doctor will discuss the test with you and answer any questions.

What shall I do after the gastroscopy?

You will be escorted to your Medicover Hospital room and allowed to rest for as long as is necessary. If you chose to have throat spray, you will be offered a cold drink when the sensation in your throat has returned to normal.

If you have received sedation, your oxygen levels, blood pressure and heart rate will be recorded. It usually takes about 30 minutes for the initial effects of sedation to wear off but some people may feel fully alert immediately after the procedure.  However, the drugs remain in your blood system for up to 24 hours and you can intermittently feel drowsy with lapses of memory.  You will need someone to escort you home and supervise you for this 24-hour period, but it is recommended to stay one night at your Medicover Hospital room.

The nurse or doctor will explain the findings on your gastroscopy and any medication or further investigations that may be required.  He or she will also inform you if you require further appointments.  If biopsies were taken, they will need to be sent to the pathology lab for further analysis.  It may take up to a fortnight for these results to be available.

Sedation can make you forgetful and you may like to have a family member or friend with you when you are given this information. Occasionally, the procedure can be performed without sedation, after having it discussed with your doctor.

What are the limitations of the screening gastroscopy?

Its quality and its interpretation are highly dependent on a variety of technical factors that may lead to a suboptimal study. Gastroenterologist refer to “blind spots” – regions difficult to visualize in most cases – which include the superior aspect of the duodenal bulb, portions of the fundus, and the lesser curvature below the incisura. Active uncontrolled bleeding, retained blood in the stomach, and retained food or antacids may also lead to an inadequate study. It should not be used for the diagnosis of esophageal motility disorders. Similarly, screening gastroscopy not a first-line test for the diagnosis of reflux esophagitis.

Dear Customers,

we would like to inform you that our Clinics will be closed on August 20th and 21st.


Dear Customers,

we would like to inform you that our Clinics will be closed on August 20th and 21st.