Gastroscopy: What to Expect Before, During & After

What Is Gastroscopy and Why Is It Done?

Gastroscopy (upper endoscopy or EGD) is a procedure that uses a thin, flexible tube with a camera to examine the inside of your esophagus, stomach, and duodenum. It helps diagnose conditions like ulcers, inflammation, celiac disease, and cancer, and can also be used to take biopsies or perform treatments.

Gastroscopy is one of the most common and valuable diagnostic procedures in medicine, performed millions of times each year worldwide. The procedure uses a gastroscope – a flexible tube approximately one meter long and about one centimeter in diameter – that contains a tiny camera and light source. This allows your doctor to see detailed, real-time images of your upper digestive tract on a monitor.

The name "gastroscopy" comes from the Greek words "gaster" (stomach) and "skopein" (to look), literally meaning "to look inside the stomach." However, the examination actually covers three areas: the esophagus (food pipe), the stomach, and the duodenum (first part of the small intestine). For this reason, the procedure is also medically known as esophagogastroduodenoscopy (EGD) or simply upper endoscopy.

Unlike X-rays or CT scans, gastroscopy provides direct visualization of the tissue lining, allowing doctors to detect subtle changes in color, texture, and structure that might indicate disease. The ability to take tissue samples (biopsies) during the same procedure makes it an invaluable diagnostic tool, as these samples can be examined under a microscope to provide definitive diagnoses.

Common reasons for gastroscopy

Your doctor may recommend a gastroscopy for various symptoms and conditions. Understanding why the procedure is needed can help reduce anxiety and ensure you're well-prepared.

• Persistent heartburn or acid reflux: To check for damage to the esophagus from stomach acid (reflux esophagitis) or Barrett's esophagus
• Difficulty swallowing (dysphagia): To identify narrowing, inflammation, or other causes
• Unexplained abdominal pain: Particularly pain in the upper abdomen that doesn't respond to treatment
• Nausea and vomiting: Especially if persistent or with blood
• Bleeding in the digestive tract: Indicated by vomiting blood or black, tarry stools
• Unexplained weight loss: To rule out serious conditions
• Iron deficiency anemia: To find hidden sources of blood loss
• Celiac disease screening: To take biopsies from the small intestine
• Monitoring known conditions: Such as Barrett's esophagus or previous ulcers

The gastroscope explained

Modern gastroscopes are remarkable pieces of medical technology. The flexible tube contains fiber-optic cables that transmit light to illuminate the digestive tract, along with a high-definition camera that sends images to a monitor. The doctor controls the direction of the tip using dials on the handle, allowing them to see in all directions and navigate around curves in the digestive tract.

The gastroscope also has a channel through which instruments can be passed – tiny forceps for taking biopsies, snares for removing polyps, and tools for treating bleeding. Carbon dioxide or air can be pumped through to gently expand the organs, making it easier to see the lining. This may cause a feeling of fullness or bloating, but it passes quickly after the procedure.

How Should You Prepare for Gastroscopy?

Preparation for gastroscopy requires fasting for at least 6 hours before the procedure – no food or drinks. If you take regular medications, you may be able to take them with a small sip of water up to 2 hours before. Inform your doctor about all medications, especially blood thinners, diabetes medications, and any allergies.

Proper preparation is crucial for a successful gastroscopy. An empty stomach allows the doctor to see clearly and reduces the risk of complications. The preparation process may seem straightforward, but following instructions carefully ensures the best possible examination.

When you receive your appointment, you'll typically get detailed instructions. However, if anything is unclear, don't hesitate to contact your healthcare provider. Being well-prepared not only ensures a better examination but also helps you feel more confident going into the procedure.

Fasting requirements

Fasting is the most important preparation step. You should not eat or drink anything for at least 6 hours before your gastroscopy. This includes:

• All solid foods, including small snacks
• Drinks of any kind (water, juice, coffee, tea)
• Chewing gum and sweets
• Smoking (can stimulate stomach acid production)

The reason for fasting is twofold: first, any food or liquid in the stomach obscures the view and makes it impossible to examine the lining properly. Second, there's a small risk that stomach contents could enter the lungs during the procedure (aspiration), which can cause serious complications. An empty stomach eliminates this risk.

Medication considerations

Managing your medications before gastroscopy requires careful planning. Some medications may need to be adjusted or temporarily stopped, while others should be continued. Here's general guidance, but always follow your doctor's specific instructions:

What to tell your doctor before the procedure

Before your gastroscopy, make sure to inform your healthcare team if any of the following apply to you:

• You have allergies to medications, especially local anesthetics (like those used at the dentist)
• You have heart problems, lung disease, or other serious health conditions
• You have had reactions to sedation in the past
• You are pregnant or might be pregnant
• You have diabetes (fasting and sedation require special planning)
• You have a bleeding disorder or take blood-thinning medications
• You have a pacemaker or implanted defibrillator
• You have had previous surgery on your esophagus or stomach

Managing anxiety about gastroscopy

It's completely normal to feel nervous about having a gastroscopy. Many people worry about the gagging sensation or feel uncomfortable about having a tube passed into their throat. Understanding what to expect and knowing that the medical team performs these procedures routinely can help.

If you're particularly anxious, let your healthcare team know. They can provide extra support, explain each step as it happens, and ensure you receive adequate sedation if needed. Many patients report that the procedure was much easier than they anticipated, and the vast majority say they would have another gastroscopy if needed.

Some practical tips for managing anxiety:

• Ask questions beforehand so you know exactly what will happen
• Bring a supportive friend or family member (they can wait for you)
• Practice slow, deep breathing techniques
• Remember that the procedure is quick and the benefits of diagnosis outweigh the brief discomfort
• Consider requesting sedation if you're very nervous

How Is Gastroscopy Performed?

During gastroscopy, you lie on your left side while a thin, flexible scope is gently guided through your mouth into your digestive tract. Local anesthetic spray numbs your throat, and sedation is offered for comfort. The procedure typically takes 10-15 minutes, and you can breathe normally throughout.

Understanding exactly what happens during a gastroscopy helps most people feel more comfortable about the procedure. The process is well-established, safe, and performed by experienced specialists who carry out many gastroscopies every day.

A typical gastroscopy involves several steps, from the initial preparation in the examination room through to the recovery period. The medical team – usually a doctor (gastroenterologist or trained physician) along with one or two nurses – will explain everything as it happens and ensure your comfort throughout.

Sedation and throat numbing

Before the procedure begins, you'll have a small cannula (thin plastic tube) inserted into a vein in your hand or arm. This allows the medical team to give you sedation and other medications if needed during the procedure.

There are two main approaches to comfort during gastroscopy:

• Throat spray alone: A local anesthetic spray is applied to the back of your throat to numb the area. This reduces the gag reflex and makes it easier to swallow the scope. The spray may taste slightly bitter and can make your throat feel swollen, but this is just the numbing effect – your airway remains clear.
• Sedation (conscious sedation): In addition to throat spray, you receive medication through the cannula that makes you relaxed and drowsy. You may not remember much of the procedure afterward. This is not general anesthesia – you remain conscious and can respond to instructions, but you're in a deeply relaxed state.

The choice between these options depends on your preference, anxiety level, and medical factors. Discuss with your doctor beforehand which approach is best for you. Most adults tolerate gastroscopy well with just throat spray, though sedation is always available if you prefer.

Children and gastroscopy

Children usually require general anesthesia for gastroscopy. Being fully asleep ensures they remain still and comfortable throughout the procedure. If your child needs a gastroscopy, you'll receive specific instructions about preparation, and a pediatric anesthesiologist will be involved in their care.

Step-by-step: What happens during the procedure

Here's what you can expect during a typical gastroscopy:

1. Positioning: You'll lie on your left side on the examination table, with your head on a pillow. This position helps any saliva or fluid drain naturally from your mouth.
2. Throat spray: The anesthetic spray is applied to the back of your throat. Wait a minute or two for it to take effect.
3. Mouthguard: A plastic mouthpiece is placed between your teeth. This protects your teeth and the scope, and has a hole for the gastroscope to pass through. Keep your teeth gently on the mouthguard throughout.
4. Scope insertion: The doctor gently guides the tip of the gastroscope to the back of your throat. You'll be asked to swallow to help the scope pass into your esophagus. This is the moment many people find most challenging, but it lasts only a few seconds.
5. Examination: The doctor slowly advances the scope while examining the lining of your esophagus, then stomach, then duodenum. Air or carbon dioxide is gently pumped in to expand the organs for better visibility. This may feel like fullness or pressure.
6. Biopsies or treatment: If needed, tiny instruments are passed through the scope to take tissue samples or perform treatments. Taking biopsies is usually painless.
7. Scope removal: The scope is slowly withdrawn, with further examination on the way out. The entire insertion-to-removal typically takes 10-15 minutes.

What you may feel during gastroscopy

Being prepared for the sensations can help you stay calm during the procedure. Here's what many people experience:

• Gagging sensation: When the scope first enters your throat, you may gag. This is a natural reflex that usually passes quickly. The throat spray helps reduce this.
• Fullness or pressure: As air is pumped in to expand your stomach, you may feel bloated. It's normal to burp during and after the procedure.
• Mild discomfort: Some people feel slight discomfort as the scope moves through, but it shouldn't be painful.
• Drowsiness: If you've had sedation, you'll feel very relaxed and may feel like you're drifting in and out of sleep.

What Treatments Can Be Performed During Gastroscopy?

Gastroscopy isn't just diagnostic – it also allows treatment of many conditions during the same procedure. Doctors can remove polyps, treat bleeding ulcers, dilate narrowed areas, remove foreign objects, place feeding tubes, and treat esophageal varices. This often eliminates the need for surgery.

One of the major advantages of gastroscopy is the ability to both diagnose and treat problems in the same session. The gastroscope's working channel allows specialized instruments to be passed through, enabling a wide range of therapeutic procedures that would otherwise require surgery.

If your doctor suspects you might need treatment during your gastroscopy, they'll discuss this beforehand. Some treatments are straightforward, while others may extend the procedure time or require special preparation (such as stopping blood-thinning medications).

Common treatments performed during gastroscopy

• Biopsy (tissue sampling): Tiny forceps are used to take small tissue samples from suspicious areas. These are sent to a laboratory for microscopic analysis. Taking biopsies is painless as the digestive tract lining has no pain nerves.
• Polyp removal (polypectomy): Polyps are growths on the lining that may become cancerous. They can be removed using a wire snare or special forceps passed through the scope.
• Treating bleeding: Bleeding from ulcers, tears, or abnormal blood vessels can be treated using various methods: injection of medication to constrict blood vessels, heat application (cauterization), or placing clips to seal the bleeding site.
• Dilation (stretching narrowed areas): If the esophagus or stomach outlet has become narrowed (stricture), a special balloon can be passed through the scope and inflated to stretch the area open. This is called dilation or dilatation.
• Foreign body removal: Objects that have been accidentally swallowed and become stuck can often be removed using special grasping tools passed through the scope.
• Treating esophageal varices: These are enlarged veins in the esophagus that can bleed dangerously. They can be treated by placing small rubber bands around them (banding or ligation), which cuts off blood flow and makes them shrink.
• Placing feeding tubes: A thin tube can be placed through the stomach wall (PEG tube) to provide nutrition directly to the stomach when someone cannot swallow.
• Stent placement: A metal or plastic mesh tube can be placed to keep a narrowed area open, often used in cancer treatment.

Balloon enteroscopy: Examining the small intestine

Sometimes doctors need to examine more of the small intestine than a standard gastroscopy can reach. In this case, a special technique called balloon enteroscopy may be used. This involves a longer endoscope with one or two inflatable balloons that grip the intestinal wall, allowing the scope to gradually advance deeper into the small intestine.

Balloon enteroscopy takes longer than standard gastroscopy – typically 45 to 90 minutes – and is usually performed under deeper sedation. It's used for conditions like obscure bleeding, small bowel tumors, or Crohn's disease affecting the small intestine.

What Happens After Gastroscopy?

After gastroscopy, you'll rest for 30-60 minutes while the throat numbness wears off. You shouldn't eat or drink for about one hour to prevent choking. If you had sedation, you'll need someone to take you home and should not drive, operate machinery, or make important decisions for 24 hours.

The recovery period after gastroscopy is generally straightforward, and most people feel back to normal within a few hours. Understanding what to expect helps you plan your day and ensures a smooth recovery.

Immediately after the procedure, you'll be taken to a recovery area where nurses will monitor your blood pressure, pulse, and oxygen levels. The time you spend here depends on whether you had sedation and how you're feeling.

Immediate post-procedure care

In the first hour after your gastroscopy:

• Rest: You'll lie down and rest while the effects of any sedation and throat spray wear off
• No eating or drinking: Wait at least one hour before having anything by mouth. Your throat is still numb, and there's a risk of food or liquid going down the wrong way
• Test swallowing: Before eating, take small sips of water to make sure you can swallow safely
• Burping is normal: The air pumped into your stomach during the procedure needs to come out – this is completely normal

If you had sedation

Sedation affects your judgment, coordination, and reaction time for up to 24 hours, even if you feel alert. For this reason:

• Arrange transport home: You must have someone accompany you home. You cannot drive, take public transport alone, or walk home by yourself
• Stay accompanied: Have a responsible adult stay with you for the rest of the day
• No driving: Do not drive any vehicle for 24 hours
• No important decisions: Avoid signing legal documents or making major financial decisions
• No alcohol: Don't drink alcohol for 24 hours as it can interact with sedation medications
• Take it easy: Rest for the remainder of the day and resume normal activities the next day

Normal symptoms after gastroscopy

It's common to experience some mild effects after gastroscopy. These are usually nothing to worry about:

• Sore throat: Mild throat discomfort is very common and usually resolves within 1-2 days. Throat lozenges or warm drinks (once you can swallow safely) may help.
• Bloating: Some abdominal distension from the air used during the procedure is normal. It usually passes within a few hours.
• Drowsiness: If you had sedation, you may feel sleepy for several hours.
• Mild nausea: Some people feel slightly queasy, especially after sedation.

When Will You Get Your Gastroscopy Results?

Your doctor can usually discuss the visual findings immediately after the procedure. If biopsies were taken, laboratory results typically take 1-3 weeks. How you receive results varies by clinic – you may be told in person, called, or asked to schedule a follow-up appointment.

Waiting for test results can be stressful, so it helps to know what to expect. The gastroscopy provides two types of information: what the doctor sees during the examination, and what laboratory analysis of any biopsies reveals.

Immediate visual findings

Once you're alert enough after the procedure, your doctor will usually come to speak with you about what they observed. They can tell you:

• Whether your esophagus, stomach, and duodenum looked normal or if there were any abnormalities
• If they found ulcers, inflammation, or other visible problems
• What biopsies were taken and why
• If any treatments were performed
• What happens next in terms of follow-up

If you've had sedation, you may not remember this conversation clearly. It's helpful to have your accompanying person present to listen, or to ask for written information you can read later.

Biopsy results

If tissue samples were taken, these are sent to a pathology laboratory where specialists examine them under a microscope. This analysis typically takes 1 to 3 weeks, though it can vary depending on the tests required and the laboratory's workload.

Biopsy results are usually communicated by the doctor who referred you for the gastroscopy. Different clinics have different systems – some will call you with results, others will send a letter, and some will ask you to book a follow-up appointment. Ask before you leave so you know what to expect.

What Are the Risks and Complications of Gastroscopy?

Gastroscopy is very safe, with serious complications occurring in less than 1 in 1,000 procedures. Rare risks include bleeding (especially after biopsies), perforation (tear) of the digestive tract, and reactions to sedation. Minor effects like sore throat are common but resolve quickly.

While it's important to understand potential complications, it's equally important to put them in perspective. Gastroscopy has been performed safely for decades, and the risk of serious problems is very low. For most people, the benefits of accurate diagnosis far outweigh the small risks involved.

Minor effects (common)

These are not really complications but normal after-effects that resolve on their own:

• Sore throat: Very common, usually mild, lasting 1-2 days
• Bloating: From air used during the procedure, passes within hours
• Mild drowsiness: If sedation was used, resolves within 24 hours

Rare complications

Serious complications are uncommon but can occur:

• Bleeding: Usually only occurs if biopsies are taken or treatments performed. In most cases, any bleeding is minor and stops on its own. Rarely, it may require further treatment or transfusion. Risk is higher in people taking blood-thinning medications.
• Perforation (tear): A very rare complication (about 1 in 3,000 diagnostic procedures) where a small hole is made in the wall of the esophagus, stomach, or duodenum. This is a serious complication that may require surgery to repair.
• Reaction to sedation: Rarely, people may have breathing difficulties or allergic reactions to sedation medications. This is why your oxygen levels are monitored throughout and the team has emergency equipment available.
• Aspiration: If the stomach isn't empty (which is why fasting is essential), there's a small risk of stomach contents entering the lungs.
• Infection: Very rare with modern disinfection procedures.
• Blood pressure drop: Can occur with sedation but is usually easily managed.

When to seek medical help after gastroscopy

Contact your healthcare provider or seek emergency care if you experience any of the following after your gastroscopy:

Are There Alternatives to Gastroscopy?

While gastroscopy is the gold standard for examining the upper digestive tract, alternatives include barium swallow X-rays, CT scans, and capsule endoscopy. However, none of these allow biopsies or treatment during the same procedure, which limits their usefulness for many conditions.

In some cases, other tests may be considered instead of or before gastroscopy. However, each alternative has limitations, and gastroscopy remains the most comprehensive and accurate method for diagnosing and treating upper GI conditions.

Alternative investigations

• Barium swallow/meal: You drink a liquid containing barium, which shows up on X-rays. Useful for identifying structural problems like narrowing or hiatus hernia, but cannot take biopsies or treat problems.
• CT scan: Provides detailed images of the digestive organs and surrounding structures. Good for detecting tumors and other abnormalities, but cannot examine the inner lining in detail or take samples.
• Capsule endoscopy: You swallow a tiny camera in a capsule that takes thousands of pictures as it travels through your digestive system. Mainly used for examining the small intestine rather than the stomach, and cannot take biopsies or perform treatments.
• Blood and stool tests: Can detect signs of bleeding, infection (like H. pylori), or celiac disease, but cannot visualize the digestive tract directly.

For most conditions affecting the esophagus, stomach, and duodenum, gastroscopy provides information that no other test can match. The ability to see directly, take tissue samples, and treat problems makes it irreplaceable for many diagnoses.