A gastroscopy is a procedure that uses a thin, flexible camera to look inside your food pipe (esophagus), stomach, and the first part of your small intestine. Doctors also call it an upper endoscopy or EGD (esophagogastroduodenoscopy). The whole exam typically takes just 5 to 10 minutes, and most people go home the same day.
Why Doctors Recommend a Gastroscopy
A gastroscopy is ordered when your doctor needs to see what’s happening inside your upper digestive tract rather than guessing from symptoms alone. The most common reasons, based on a large national survey of procedures, break down like this:
- Reflux or heartburn symptoms: 28.3% of procedures
- Alarm symptoms (unexplained weight loss, persistent vomiting, or signs of something more serious): 27.7%
- Difficulty swallowing: 20.5%
- Signs of bleeding (vomiting blood, dark stools, or unexplained anemia): 20.4%
- Abdominal pain or bloating: 20.1%
Beyond investigating symptoms, gastroscopies are also used for ongoing surveillance. People who have a condition called Barrett’s esophagus, where stomach acid has changed the lining of the food pipe over time, need periodic checks to watch for precancerous changes. A smaller number of procedures are done purely for screening in people at high risk.
How to Prepare
Your stomach needs to be completely empty so the camera has a clear view and the procedure is safe. The standard instruction is to stop eating and drinking at midnight the night before. You can take small sips of water up until four hours before your appointment, but nothing at all in that final four-hour window. If anything is in your stomach during those last hours, even water or chewing gum, the procedure will likely be delayed or canceled.
If you take blood thinners, your care team will typically contact you about two weeks before the procedure to discuss whether to pause or adjust them. Diabetes medications also require changes: most oral diabetes drugs are held the morning of the procedure, and if you use insulin, you’ll generally reduce your long-acting dose by half. People taking weekly injectable medications like semaglutide or tirzepatide (commonly used for diabetes or weight loss) are usually told to stop at least seven days beforehand, because these drugs slow stomach emptying significantly.
What Happens During the Procedure
You’ll lie on your left side. Before the scope goes in, you’ll choose between two comfort options (or sometimes a combination): a numbing spray applied to the back of your throat, or sedation delivered through an IV line. Research shows that most people who aren’t particularly anxious about the procedure do well with just the throat spray and prefer to skip sedation. Among people who are anxious, sedation tends to make the experience more comfortable. In studies where patients were given a genuine choice, about three-quarters in both groups said they’d make the same decision again.
A small plastic guard is placed between your teeth to keep your mouth open and protect the scope. The gastroscope, a flexible tube roughly the width of a finger with a light and camera at the tip, is guided past your throat as you swallow. It’s then slowly advanced through your food pipe, into your stomach, and down to the entrance of your small intestine. Air is gently pumped in to open up the walls so the doctor can see clearly. This can cause a feeling of fullness or bloating, but it’s temporary.
If anything looks unusual, the doctor can pass tiny instruments through the scope to take tissue samples (biopsies). You won’t feel the biopsies being taken. The scope can also suction out air and fluid before it’s withdrawn.
How It Feels
If you had the throat spray only, you’ll be fully alert throughout. Most people describe a gagging sensation when the scope first passes the throat, which eases once it moves deeper. You can breathe normally the entire time because the scope goes down your food pipe, not your windpipe. If you received sedation, you’ll likely remember very little or nothing at all. Either way, the procedure itself is not painful, though it can be uncomfortable.
Risks and Complications
Gastroscopy is one of the safest procedures in medicine when done for diagnostic purposes. The risk of a perforation (a small tear in the lining of the digestive tract) during a standard diagnostic gastroscopy is about 0.03%, or roughly 3 in 10,000 procedures. The risk of death is approximately 1 in 100,000. Significant bleeding from a diagnostic exam alone is rare. When the procedure involves treatment rather than just looking, such as removing growths or stretching a narrowed area, complication rates are higher but still relatively low.
The most common aftereffects aren’t true complications. A mild sore throat, bloating from the air used during the exam, and slight nausea from sedation are all normal and resolve within a day.
Recovery and Getting Home
If you had sedation, current guidelines recommend avoiding driving for 24 hours afterward, though some researchers have questioned whether this window is longer than necessary given newer, shorter-acting sedation drugs. One study found that patients needed a median of about 20 hours to feel completely back to normal after sedation. You’ll need someone to drive you home, and most facilities won’t discharge you alone.
If you had only the throat spray, you can usually leave on your own shortly after the procedure. Regardless of which option you chose, most people can eat within a few hours once the numbness in their throat has worn off. Starting with soft foods and small sips of water is a reasonable approach. Most people return to work and normal activities the next day.
Understanding Your Results
Your doctor can often share initial findings right after the procedure, since they’ve just seen the images in real time. Visible things like inflammation, ulcers, or structural changes are apparent immediately. If tissue samples were taken, those need to be processed and examined under a microscope by a pathologist.
Biopsy results generally take between 2 and 10 days. Guidelines from major pathology organizations recommend that straightforward biopsy results be finalized within 2 to 5 days, though more complex cases can take longer. Your doctor’s office will typically contact you with results, or you may need to schedule a follow-up appointment to discuss what was found and whether any treatment or further monitoring is needed.