Mount Alvernia Medical Centre D
820 Thomson Road, #08-52, Singapore 574623
Tel: +65 6252 5257 | Fax: +65 6252 5227

Mount Elizabeth Novena Specialist Centre
38 Irrawaddy Road, #09-36, Singapore 329563
Tel: +65 6684 0992 | Fax: +65 6684 0892



What is gastroscopy?

A gastroscopy, sometimes referred to as an endoscopy, is a test that allows the doctor to examine the inner lining of the upper gut (gastrointestinal tract), namely the oesophagus (swallowing tube),stomach, and duodenum (first part of the small intestines). The doctor uses an endoscope to perform this procedure. An endoscope is a thin, flexible, fibreoptic telescope. It is about as thick as a little finger. The endoscope is passed through the mouth, into the oesophagus and down towards the stomach and duodenum. The endoscope is equipped with a torchlight and tiny video camera at the tip. It is connected to a monitor so that the doctor can view the contents.


When is gastroscopy performed?

A gastroscopy is usually performed to investigate the following symptoms:
  • Recurrent indigestion
  • Recurrent heartburn
  • Upper abdominal pain or discomfort
  • Difficulty swallowing
  • Repeated vomiting
  • Vomiting blood or passing foul-smelling, black, tarry stools

A gastroscopy can be used to confirm these conditions:

  • Oesohagitis (inflammation of the oesophagus)
  • Gastritis or duodenitis (inflammation of the stomach or duodenum)
  • Stomach or duodenal ulcers
  • Cancer of the stomach or oesophagus

 How is gastroscopy performed?

Gastroscopy is usually performed as an outpatient ‘day case’. The patient is required to fast for 6 hours before the procedure. Your doctor may numb the back of your throat using local anaesthetic. To help you relax, your doctor may also give you a sedative intravenously. You will be positioned on your side and a plastic mouth guard will be put between your teeth. This is to protect your teeth and prevent you from biting the endoscope.

The endoscope will then be inserted into your mouth and gently pushed further down to the oesopagus and subsequently into your stomach and duodenum. The tiny video camera will send real time images to a monitor to allow your doctor to look out for any abnormalities. Air is also pumped through the endoscope to distend your stomach. This will make the stomach lining easier to see. You may feel ‘full’ and wanting to belch. A biopsy may be taken from the lining of the gut for laboratory testing. This is a painless process. Once completed, your doctor will withdraw the endoscope gently until it is pulled out. The whole procedure usually takes about 10 minutes. However, it is recommended that you set aside at least 2 hours for the whole appointment, for preparation,sedation(if you have one), for the gastroscopy itself, and recovery.

What are the potential complications from gastroscopy?

Gastroscopy is a very safe and effective test. It does not usually hurt but may be a little uncomfortable especially when the endoscope passes through the back of your throat. You may experience a mild sore throat for a day or two.

There is also a very slight risk of chest infection, stroke or heart attack after a gastroscopy. This tends to happen in older people with poor health. These serious complications are very rare in the majority of patients who are otherwise healthy.

The endoscope rarely causes damage to the gut, such as bleeding, perforation or tears (approximately 1 in 10, 000 cases). This will require urgent treatment. Should you experience any of the following symptoms within 48 hours of the procedure, do seek medical attention immediately:

  • Severe abdominal pain
  • Fever
  • Breathing difficulties
  • Vomiting blood or passing of black, tarry stools

Some people may also have an allergic reaction to the sedative, but this is very rare.

Special precautions

If your doctor gives you an intravenous sedative, you may take a little longer to be ready to go home. It is preferable that an adult accompanies you home and stays with you for 24 hours. You should not drive, operate machinery or drink alcohol for at least 24 hours after the sedative is given. However,you can resume your normal diet. Most people will be able to return to normal activities after 24 hours.