Endoscopy
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Overview
An upper GI endoscopy — also called gastroscopy or OGD — is a procedure that lets a gastroenterologist directly examine the food pipe (oesophagus), stomach, and the first part of the small intestine (duodenum). A small flexible camera on a thin tube is passed through the mouth, with the patient under light sedation.
It is one of the most important tests in gastroenterology. Where imaging or blood tests give indirect clues, endoscopy lets the doctor actually see what’s happening — and take biopsies or treat problems in the same session.
What is this test?
A thin, flexible tube (about the thickness of a finger) with a high-definition camera and light at the end is passed through the mouth and down the food pipe. The doctor sees the lining of the oesophagus, stomach, and duodenum on a screen in real time. Small instruments can be passed through the scope to take biopsies, remove polyps, stop bleeding, or stretch narrowed areas — all in the same procedure.
Why your doctor may order it
- Persistent acidity, heartburn, or reflux that doesn't respond to medication
- Difficulty or pain in swallowing
- Persistent vomiting or nausea
- Gale and Graham Wright Prostate Centr
- Investigating anaemia of unclear cause (looking for chronic blood loss)
- GI bleeding — vomiting blood or passing black stools
- Unexplained weight loss with GI symptoms
- Screening in people with risk factors for stomach or oesophageal cancer
- Testing for H. pylori (a common cause of ulcers)
How long does it take?
The endoscopy itself takes about 10 to 20 minutes. With sedation recovery and observation, plan for 2 to 3 hours at the hospital.
How to prepare
- Fast for 6 to 8 hours before the procedure. No food, no milk, no juice. Plain water sips up to 2 hours before are usually allowed.
- Tell the team about all medications you take, especially blood thinners, iron tablets, and antacids. Some may need to be stopped a few days before.
- Tell us about any allergies, particularly to anaesthetic agents.
- Tell us about heart, lung, or sleep apnoea problems — they affect sedation planning.
- Arrange for someone to accompany you home — you cannot drive for 24 hours after sedation.
- Bring your prescription, ID, previous endoscopy reports, and your insurance card if applicable.
What to expect during the test
You change into a hospital gown and a cannula is placed in your arm. The team will go through what to expect and answer your questions. You lie on your left side. A throat spray may be used to numb the back of the throat. Sedation is given through the cannula and you become drowsy within a minute. A mouth guard is placed between your teeth, and the scope is gently passed through your mouth and down the food pipe. You can breathe normally throughout. Most people remember little or nothing of the procedure.
The doctor examines the lining and may take small biopsies (you do not feel these) or treat any problem found. The scope is then withdrawn.
After the test
- You rest in the recovery area for 30 to 60 minutes while the sedation wears off.
- Your throat may feel sore or numb for a few hours. Some bloating from the air pumped in during the scope is normal — burping it out helps.
- Wait until your throat feels normal again before eating or drinking (usually 1 hour after the scope). Start with small sips of water, then light food.
- Do not drive, operate machinery, sign legal documents, or drink alcohol for 24 hours after sedation.
- Watch for warning signs and call us if you have: severe or worsening abdominal pain, vomiting blood, black tarry stools, fever, or breathing difficulty.
- The endoscopy report is usually given the same day. Biopsy results take 3 to 7 days.
Do's and Don'ts
- Fast strictly as instructed.
- Arrange a responsible adult to take you home.
- Rest for 24 hours after the procedure.
- Eat light food after the procedure — start with soft, bland items.
- Call us straight away if you develop severe pain, fever, vomiting blood, or black stools after the procedure.
- Don't eat or drink during the fasting period.
- Don't take blood thinners unless your doctor has confirmed it is safe.
- Don't drive or make important decisions for 24 hours after sedation.
- Don't ignore warning symptoms after the procedure — complications are rare but need prompt attention.
- Don't drink alcohol on the day of the procedure.
Understanding your results
The endoscopy report describes the appearance of the oesophagus, stomach, and duodenum, with photos of any abnormality. Common findings include gastritis (inflammation), ulcers, hiatus hernia, reflux changes, polyps, or evidence of H. pylori infection. Biopsy results, if taken, take a few days. Your gastroenterologist will discuss the findings and explain what they mean. Most findings at endoscopy are treatable — and many are reassuring.
Frequently asked questions
With sedation, most people remember little of the procedure. Without sedation, the main discomfort is gagging during the initial passage of the scope. Sedation makes the experience much easier and is what we usually recommend.
Yes — some patients prefer it, especially if they need to drive afterwards. A throat spray is used to numb the gag reflex. The scope is then passed without IV medication.
No. The lining of the stomach and food pipe does not feel pain in the way skin does. Biopsies are painless and safe.
It depends on the findings. Some conditions (like Barrett's oesophagus or large gastric polyps) need regular surveillance. Most acidity and ulcer cases do not need repeat scopes unless symptoms persist.
Yes — endoscopy with biopsy is one of the most reliable tests for stomach and oesophageal cancer. Catching these early dramatically improves outcomes.