What is gastroscopy?
Gastroscopy is an examination of the inside of the gullet, stomach
and duodenum. It is performed by using a thin, flexible fibre-optic
instrument that is passed through the mouth and allows the doctor to
see whether there is any damage to the lining of the oesophagus
(gullet) or stomach, and whether there are any ulcers in the stomach
The GP will decide when drug treatment alone is sufficient or
whether an investigation by gastroscopy at the local hospital is
The procedure is painless and is usually done under a light sedative
as a day-case patient in a specialised endoscopy unit.
Occasionally, after a discussion with the endoscopist, the procedure
will be performed without sedation. When sedation is used, the
patient will not be able to drive or operate machinery for the rest
of the day.
Anyone suffering from stomach problems should consult a doctor who
will, in most cases, treat the symptoms without a major examination.
How is a gastroscopy performed?
After explaining the procedure, the endoscopist will spray the back
of the throat with a local anaesthetic. This is similar to the
anaesthetic used by dentists. It numbs the throat and may make it
difficult to swallow. When sedation is used, it is not a full
anaesthetic and the patient will still be conscious and aware. A
nurse will lie the patient on their left side and the endoscopist
will then gently place the end of the instrument into the mouth and
ask the patient to swallow it, which feels like swallowing a large
piece of food.
The endoscopist may need to put some air into the stomach to perform
the examination effectively and this can cause discomfort or even a
need to belch. This is perfectly normal.
The endoscopist will closely examine the lining of the gullet,
stomach and duodenum to identify the cause of the symptoms. It will
take about 10 to 15 minutes.
Why is gastroscopy useful?
The doctor can study the mucous membrane of the stomach from the top
to the bottom, and see irritation, wounds, or tumours. Gastroscopy
is effective, and has now replaced the use of X-rays in many cases.
It helps the doctor see any abnormalities in the gullet, the stomach
and the duodenum. It is precise and safe.
Through the gastroscope, the doctor can take samples or photographs
of the mucous membrane. The most modern gastroscopes can also show
the areas in the stomach on a TV screen, so that the mucous membrane
can be studied thoroughly. This can be recorded on a videotape, and
used for later comparison.
Patients are often given a gastroscopic examination because of their
indigestion symptoms, which can usually be treated with tablets.
Occasionally, the cause of indigestion is an ulcer and it is now
known that many ulcers are due to bacterial infection in the
A biopsy (a small piece of the lining of the stomach) may be removed
during an endoscopy and examined under the microscope in the
laboratory to pinpoint an infection.
A very small number of patients with indigestion will turn out to
have cancer and, again, the diagnosis can be made accurately by
biopsy. Further investigation can then be planned to ensure the most
Can gastroscopy be used to examine other parts of the body?
On the way down towards the stomach, gastroscopy can also be used to
examine the mucous membrane of the gullet - there are several
diseases with symptoms that are easily mistaken for diseases in the
stomach. If this examination is performed independently it is called
oesophagoscopy, after oesophagus, the medical name for the gullet.
How far can a gastroscope see?
A gastroscope can only examine the lining of the oesophagus (gullet)
stomach and duodenum. It will detect conditions in those organs that
are causing symptoms but will not, for example, detect gallstones or
Are there other uses for gastroscopy?
An increasing use for gastroscopy is to obtain biopsies from the top
of the small bowel, mainly to rule out a condition called coeliac
disease. This is usually arranged at a hospital clinic but in some
areas the test may be available to local doctors.
Why doesn't my doctor just send me for an X-ray?
This is a good point. Barium meals were used for many years for the
diagnosis of indigestion symptoms. However, the small disadvantages
of gastroscopy - special units, day-case admission and the need for
sedation - are far outweighed by the increased accuracy of diagnosis
and the ability to take biopsies at gastroscopy. As a result
relatively few barium meals are performed nowadays.
Is gastroscopy safe?
All procedures carry some risk but outpatient diagnostic gastroscopy
is very safe. Minor complications are uncommon and major
complications are very rare.