Gastroscopy (Oesophago-gastro-duodenoscopy (OGD) / upper GI endoscopy)
A test where a thin, flexible camera is passed through the mouth to look at the lining of the gullet, stomach and the first part of the small bowel, find the cause of symptoms and take samples.
✓ Medically reviewed by a GMC-registered consultant · last reviewed September 2026 · next review September 2027 · how we review
In short
- A gastroscopy lets the lining of the gullet, stomach and upper small bowel be examined directly, with samples taken and some problems treated in the same test.
- It only looks at the upper gut, and a normal test does not rule out every cause of symptoms, so ongoing problems should still be reviewed.
- It is a quick day-case test; camera findings are often explained on the day, but biopsy results take about 1–2 weeks.
- You usually choose between a numbing throat spray (awake) or sedation; if you have sedation you must arrange someone to take you home and not drive for 24 hours.
A plain-English summary. The detail — including risks and recovery — is below.
At a glance
A general guide. Your specialist will give you advice for your situation.
Looks directly at the lining of the gullet, stomach and upper small bowel
People who are too unwell or unstable to undergo the test safely, until their condition is optimised.
You rest while sedation wears off or throat numbness settles. If you had throat spray, you must not eat or drink until the numbness has gone (usually...
Clear written instructions and a named contact or unit number for problems at home.
You rest while sedation wears off or throat numbness settles. If you had throat spray, you must not eat or drink...
You can eat and drink once any throat numbness has worn off. If you had sedation, go home with a responsible...
Most people return to normal activities and work. A mild sore throat and a little bloating usually settle within a...
Results from any biopsies are usually ready and explained by your team, along with any plan for treatment or a...
What is a gastroscopy?
A gastroscopy is a test that lets a doctor or specialist nurse (the endoscopist) look directly at the lining of your upper digestive system — the gullet (oesophagus), stomach and the first part of the small bowel (duodenum). A long, thin, flexible tube with a tiny camera and light is gently passed through your mouth, with the pictures shown on a screen. It is also called an OGD or upper GI endoscopy.
It is used to find the cause of symptoms such as persistent heartburn or indigestion, difficulty or pain when swallowing, ongoing tummy pain, feeling sick, unexplained weight loss, or anaemia; to check for and monitor conditions such as Barrett's oesophagus; and to treat some problems, for example a bleeding ulcer. During the test the endoscopist can take small tissue samples (biopsies), test for the Helicobacter pylori bacterium, and carry out certain treatments.
A gastroscopy gives a direct, detailed view of the upper gut, but it does not look at the rest of the bowel, and a normal test does not rule out every cause of symptoms. It is a quick test, often over in minutes, but the experience varies depending on whether you choose throat spray or sedation.
Types, options & approaches
There may be different ways to do this. The right approach depends on the clinical question and your circumstances.
Throat spray compared with sedation
| Throat spray | Sedation | |
|---|---|---|
| You are | Fully awake | Relaxed and drowsy |
| Memory of test | Usually remember it | May remember little |
| Recovery | Minimal | A few hours; rest of day off |
| Driving / escort | Can usually drive home | No driving 24h; need an escort |
| Extra risks | Very few | Small breathing/heart risks |
Neither option is 'better' — it depends on your preference, anxiety and health. You can discuss which suits you, and a small number of people need an anaesthetist-led approach.
Preparing for your procedure
- Do not eat for about 6 hours and avoid drinks for about 2 hours before the test (follow the exact fasting times your unit gives), so the stomach is empty and the view is clear.
- Tell the unit about all your medicines, especially blood thinners, diabetes medicines, and acid-reducing tablets, as some need stopping or adjusting beforehand.
- Mention heart, lung or kidney conditions, sleep apnoea, or any reaction to sedation, as these affect your sedation choice and monitoring.
- Decide in advance whether you want throat spray or sedation, and discuss the pros and cons with the team.
- Remove dentures, and tell the team about loose teeth or crowns before the test.
- If you choose sedation, arrange for a responsible adult to take you home and stay with you, and do not plan to drive, work or sign anything important for 24 hours.
- Allow a couple of hours for the appointment, including preparation and recovery time.
What happens
After checking your details and consent, you may have your throat numbed with an anaesthetic spray, or sedation given through a small cannula in your arm, depending on your choice. You lie on your left side, a plastic mouth guard protects your teeth and the camera, and a clip on your finger monitors your pulse and oxygen.
The endoscopist gently passes the flexible camera through your mouth and down into the gullet, stomach and duodenum. A little air is used to open up the view, which can make you feel bloated or want to burp — this is normal. You can breathe normally throughout; the camera does not block your airway. If needed, small usually not painful samples are taken or treatment is given.
The test itself usually takes only about 5–15 minutes. Afterwards you rest until any sedation wears off or the throat numbness settles. The endoscopist can often tell you what they saw on the day, while results from any biopsies follow later.
Is this procedure right for me?
A good consultation should explore whether it's the right choice for you now — including reasons to wait or consider something else.
May not be suitable if…
- People who are too unwell or unstable to undergo the test safely, until their condition is optimised.
- Suspected perforation of the gut, where gastroscopy can be dangerous and other management is needed first.
- When symptoms are clearly better assessed another way, or when a trial of treatment or a Helicobacter pylori test is the appropriate first step.
- People who cannot safely fast or tolerate the test, where an alternative approach may be more suitable.
Delay or rearrange if…
- You have not been able to fast properly, as a full stomach makes the test unsafe and unclear.
- Your blood thinners or diabetes medicines have not been properly planned around the test.
- You have an active chest infection or are acutely unwell, unless the test is urgent.
- Pregnancy, unless the test is genuinely needed and the timing has been discussed.
- You cannot arrange a responsible adult to take you home if you have chosen sedation.
Alternatives to discuss
- No test, or a trial of treatment, if symptoms are mild and low-risk.
- A breath or stool test for Helicobacter pylori, which may guide treatment without a camera test.
- Acid-reducing medicines and lifestyle measures as a first step for typical reflux in lower-risk people.
- Other imaging, such as an ultrasound, CT scan or a barium swallow, depending on the symptom.
- Going through an NHS pathway rather than self-funding, where time allows.
Before you decide
Use this as a shared-decision checklist. The aim is not just “can this be done?”, but whether it is right for you, now, with the risks and alternatives clearly understood.
What matters most to me?
Think about symptoms, daily life, work, caring responsibilities, sport, fertility, travel, appearance and anxiety — the right choice depends on your priorities, not just the medical facts.
What are all my options?
Ask about waiting, monitoring, medicines, rehabilitation, a smaller or larger procedure, a different test, NHS referral, or a second opinion where that would help.
What would make me pause?
Active infection, pregnancy, unstable medical problems, smoking, medicines that increase bleeding, poor support at home, or feeling pressured are all reasons to slow down and get tailored advice.
What happens if I do nothing today?
For some problems, waiting is safe; for others, delay can make treatment harder. A good consultation should explain the trade-off in plain English.
Comfort, sedation or contrast choices
If local anaesthetic, sedation, contrast or pain relief is used, ask what is planned, why, and what it means afterwards.
Benefits
- Looks directly at the lining of the gullet, stomach and upper small bowel
- Can find the cause of heartburn, swallowing problems, pain, sickness, weight loss or anaemia
- Can take samples and test for the Helicobacter pylori bacterium in the same test
- Can treat some problems on the spot, such as a bleeding ulcer or a narrowed gullet
- A clear, normal test can be reassuring and reduce the need for other investigations
Risks & complications
- A sore or scratchy throat for a day or two afterwards
- Bloating, wind or burping from the air used during the test
- Feeling tired or groggy for the rest of the day if you have sedation
- Mild discomfort or gagging during an awake test with throat spray
- A small amount of bleeding, especially if a biopsy was taken or treatment given
- An incomplete or unclear test if the stomach is not empty enough, sometimes needing a repeat
- A cause of symptoms being missed, as the test only sees the upper gut and not everything
- Breathing, heart-rate or blood-pressure effects from sedation that need monitoring
- A tear (perforation) in the gullet, stomach or duodenum, which can need urgent treatment or an operation
- Significant bleeding that needs treatment, admission or a transfusion
- A serious reaction to the sedation
- A chest infection, for example if stomach contents are breathed into the lungs (aspiration)
- Damage to teeth, crowns or dental work
A gastroscopy is generally low-risk and quick, but the serious risks — a tear in the gut lining and significant bleeding — are real, and slightly higher when treatment is carried out. Sedation adds small risks to breathing and the heart, which is why fasting and monitoring matter. The other key limitation is that it only examines the upper gut, so a normal test does not explain symptoms coming from elsewhere. Ask how a complication would be handled and what happens if the test is normal but symptoms continue.
Published figures to discuss
Serious complications are uncommon and are higher for therapeutic procedures (such as treating a bleeding ulcer or stretching a narrowing) than for a simple diagnostic test. Risk also depends on the patient's health, whether they fasted properly, and the type of sedation used. Many quoted figures come from individual units; the ranges below are cautious and source-defensible rather than exact.
| Figure | Reported range | How to interpret it | Source / confidence |
|---|---|---|---|
| Perforation or significant bleeding (diagnostic test) | Rare — around 1 in 2,500 for a straightforward diagnostic gastroscopy | Higher when treatment such as dilatation or stopping a bleed is carried out; may need urgent treatment, admission, a transfusion or an operation. | NHS — Gastroscopy: risksnhs.ukPublished figure |
| Sedation-related breathing or heart effects | Uncommon; risk rises with deeper sedation and in people with heart, lung or sleep-apnoea conditions | Monitored throughout with oxygen and observation; fasting reduces the risk of breathing in stomach contents. | NHS — Gastroscopy: risksnhs.ukSource-linked context |
| Sore throat and bloating | Common — affects many people for a day or two | Expected after-effects rather than complications; settle on their own. | NHS — Gastroscopy: risksnhs.ukSource-linked context |
These are literature figures, not a personalised prediction. Your own risks and likely benefits depend on your circumstances, your health, and how your care is carried out and followed up.
What happens afterwards
Most people feel back to normal by the next day. There is no wound to heal, but you may have a sore throat and bloating, and if you had sedation you will need to take it easy and not drive for 24 hours. The main thing you may be waiting for is the biopsy result.
- A mild sore or scratchy throat for a day or two
- Bloating, wind or burping that eases as trapped air passes
- Feeling tired or 'not quite yourself' for the rest of the day after sedation
- Mild discomfort after a biopsy, settling quickly
Aftercare
- If you had throat spray, do not eat or drink until the numbness has fully worn off (about an hour) to avoid choking.
- Start with soft foods and cool drinks if your throat is sore, and eat normally as it settles.
- If you had sedation, have a responsible adult with you and do not drive, operate machinery, drink alcohol or make important decisions for 24 hours.
- Rest for the remainder of the day and resume normal activities the next day if you feel well.
- Restart any medicines, including blood thinners, only as your team advised.
- Make a note of what the endoscopist told you and when and how you will get any biopsy results.
- Keep the unit's contact number to hand and use it if you have any warning signs.
- Fasting instructions understood (no food ~6h, no drink ~2h before)
- Blood thinners and diabetes medicines discussed and adjusted if needed
- Sedation or throat-spray choice decided
- A responsible adult to take you home and stay 24 hours if you choose sedation
- Dentures removable and loose teeth/crowns mentioned
- The unit's contact number saved for after the test
- Clear plan for how you will get your biopsy results
⚠ Get urgent help if…
- Severe or worsening chest, throat or tummy pain after the test
- Vomiting blood, or bringing up material that looks like coffee grounds
- Black, tarry stools
- Difficulty or pain on breathing, or new shortness of breath
- A high temperature, chills or feeling very unwell
- Difficulty swallowing your own saliva, or severe neck or chest swelling
- Any symptom your unit specifically warned you to report — contact them or seek urgent care
Who to contact: your clinician, clinic or test provider first (keep their number to hand). For urgent advice when you can't reach them, call NHS 111. In an emergency, call 999.
General guidance — it doesn't replace the specific advice your specialist gives you.
Results & realistic expectations
Often the endoscopist can tell you what they saw on the day — for example whether the lining looked normal, whether there is inflammation, an ulcer, or signs of Barrett's oesophagus. Results from biopsies, including tests for Helicobacter pylori or for coeliac disease, are examined in the laboratory and usually take about 1–2 weeks.
A normal gastroscopy is reassuring for the upper gut, but it only examines that part of the digestive system, so it does not rule out problems lower down or elsewhere. If your symptoms continue despite a normal result, go back to your doctor. Your team should explain what the findings mean for you, including any treatment, repeat test, or interval for future surveillance.
A gastroscopy reflects the state of your upper gut on the day. How long the reassurance lasts depends on your situation: a one-off test for settled symptoms may not need repeating, while people with Barrett's oesophagus or other higher-risk conditions are usually re-examined at set intervals. Your team will advise; new or changing symptoms should be reviewed sooner rather than waiting for the next planned test.
Related tests, treatments or support
A gastroscopy may be combined with other tests depending on your symptoms — for example blood tests, a breath or stool test for Helicobacter pylori, an ultrasound or CT scan, or a colonoscopy if symptoms could be coming from the lower bowel. Your team should explain how the tests fit together rather than doing them in isolation.
Follow-up & long-term care
Camera findings are often discussed on the day, but you should be told clearly how and when you will receive any biopsy results — usually within a couple of weeks — and who will explain them. Follow-up may include treatment (such as acid-reducing medicines or treatment for Helicobacter pylori), a planned repeat test, surveillance, or referral. Chase your results if you have not heard within the expected time.
- Attend any planned surveillance gastroscopies at the interval your team recommends, for example for Barrett's oesophagus.
- Take and complete any prescribed treatment, such as acid-reducing medicines or Helicobacter pylori treatment, and any follow-up test to confirm it worked.
- Report new or changing upper-gut symptoms promptly rather than waiting for the next scheduled test.
Repeat, follow-on and what comes next
- A test done on a stomach that was not empty enough may need to be repeated.
- Surveillance gastroscopies are often planned at set intervals for higher-risk conditions such as Barrett's oesophagus.
- Some treatments, such as stretching a narrowed gullet, may need to be repeated over time.
- Ongoing or new symptoms after a normal test should be reviewed rather than assumed to be nothing.
Ask what happens if the result is unclear or needs repeating, and what is included if further tests or follow-up are needed.
What good aftercare looks like
- Clear written instructions and a named contact or unit number for problems at home.
- Specific warning signs explained (vomiting blood, black stools, severe pain, breathing difficulty) with what to do.
- A defined process and timeframe for biopsy results, with someone to explain them.
- A clear plan for any treatment, repeat test or surveillance interval.
- Advice to seek review if symptoms continue despite a normal result.
What affects the cost
Costs vary a great deal between people and providers, and we don't publish prices. What matters is understanding what drives the cost and making sure your quote is complete. The main things that affect it:
- The endoscopist's fee and the endoscopy unit/facility fee
- Whether sedation is used and the level of monitoring needed
- Whether biopsies are taken or treatment given during the test
- Laboratory fees for examining any samples and Helicobacter pylori testing
- Same-day reporting of camera findings versus standard turnaround for biopsies
- Any follow-up consultation to explain results and plan next steps
- Whether a repeat or alternative test is needed if the examination is incomplete
- The endoscopist's fee and the unit/facility fee
- Sedation and monitoring costs, or whether throat spray is used
- The cost of biopsies and of laboratory analysis of any samples
- Whether a consultation to explain results is included
- The expected time for biopsy results and who will give them
- What happens (and what it costs) if the test is incomplete or needs repeating
- What happens, and who is responsible, if a complication occurs
- The cancellation and rebooking policy
On the NHS? Gastroscopy is widely available on the NHS for symptoms and surveillance when clinically indicated; private access is mainly used for speed or choice and usually still needs a referral.
You're entitled to your total cost in writing — including reports, follow-up and what happens if the result is inconclusive — before you decide.
Consent traps and marketing red flags
These are not small details. They are often where patients lose choice, time to reflect, or realistic expectations.
Consent traps
- Not explaining the small but real risks of perforation and bleeding, especially with treatment.
- Not discussing throat spray versus sedation and the 24-hour driving and escort rules for sedation.
- Implying the test rules out all causes of symptoms, when it only sees the upper gut.
- No clear plan for who gives the biopsy results and by when.
- No written aftercare advice or emergency contact for problems at home.
Marketing red flags
- Describing gastroscopy as 'risk-free' or 'usually not painful' without mentioning real risks.
- Implying a normal upper-gut test guarantees nothing is wrong anywhere in the digestive system.
- Pushing private gastroscopy without first considering whether a Helicobacter pylori test or a treatment trial is appropriate.
- No information on the unit's quality or safety standards.
- No clear arrangement for managing a complication out of hours.
Choosing a specialist safely
- Check the specialist is on the GMC Specialist Register for this area.
- Make sure they work at a CQC-registered service, and look for membership of the relevant Royal College or professional body.
- You're entitled to time to consider and to have your questions answered before you agree — the specialist who looks after you should explain it, not a salesperson.
- Be wary of pressure: time-limited offers or deposits taken before you've had time to think are red flags, not bargains.
- You're entitled to your total cost in writing — including any follow-up — before you decide.
Questions to ask your medical professional
Take this to your consultation. A good specialist will welcome every one of these.
- Do I definitely need a gastroscopy, or would a different test answer the question?
- Would you recommend throat spray or sedation for me, and why?
- How should I manage my blood thinners or diabetes medicines beforehand?
- What happens if you take a biopsy or need to treat something during the test?
- What happens if the test is normal but my symptoms continue?
- When and how will I get my biopsy results, and who will explain them?
- Are you on the GMC Specialist Register for this area, and which Royal College or professional body are you a member of?
- Will you be the specialist who carries out my procedure, and who looks after me afterwards?
- What are the risks for someone like me, and how often do your own patients have a problem or need it repeated or redone?
- What does a realistic result look like — and what can this procedure not achieve?
- What are my options, including waiting, doing nothing for now, or choosing a different approach?
- Can I have written information, results and aftercare instructions in a format I can use, including any accessibility or communication support I need?
- What is the total cost in writing, including any follow-ups, and how much time do I have to decide?
Frequently asked questions
Can I have a gastroscopy on the NHS?
Is a gastroscopy painful?
Should I choose throat spray or sedation?
Do I need to stop eating beforehand?
When will I get my results?
What are the chances of a serious complication?
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How we made this page
Medically reviewed by a GMC-registered consultant. Written in plain English, checked against NHS, NICE, GMC and relevant Royal College / specialist-society guidance, and kept under review. No clinic paid to appear on this page, and we publish no pricing. This is general information to help you prepare — it is not a substitute for advice from your own clinician. How we review our guides →
Source hierarchy: UK regulator and NHS/NICE guidance first, then relevant Royal College or specialist-society guidance, then peer-reviewed evidence for procedure-specific figures where available.
Sources & standards: NHS — Gastroscopy NHS — Gastroscopy: risks British Society of Gastroenterology — endoscopy guidelines BSG guidelines on sedation in gastrointestinal endoscopy (2023) JAG — quality and safety in GI endoscopy NICE — guidance and topics on dyspepsia and endoscopy
Reviews reflect patients' experience of care, not clinical outcomes. For procedure volumes and outcome data see PHIN.
Last medically reviewed 2026-09-21. Spotted something wrong or out of date? Report an error in this guide.
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