Gastroscopy Preparation Guide: What to Know Before an OGD Procedure & Endoscopy Procedure
Last update : 13 Aug 2026
The right preparation is important to ensure a successful esophagogastroduodenoscopy (OGD). From fasting rules to medication management, you need to be aware of different areas.
Key Takeaways
- Fasting is mandatory: You must stop eating solid foods 6 to 8 hours before the test and cease all clear liquids at least 4 hours prior to prevent severe complications during sedation.
- Medication adjustments are crucial: Certain medications, including blood thinners, NSAIDs, diabetes treatments, and weight-loss drugs (like Ozempic), must be modified or paused days in advance under your doctor’s guidance.
- Diet changes start early: Patients need to switch to a low-fiber diet 2 to 3 days before the procedure and completely avoid alcohol, smoking, chewing gum, and mints on the day of the test.
- Post-procedure restrictions apply: Because conscious sedation impairs your reflexes and judgment for up to 24 hours, you cannot drive, work, or make major decisions on the day of your procedure.
Esophagogastroduodenoscopy (OGD) (also known as upper endoscopy or gastroscopy) refers to a test that examines the lining of esophagus, stomach, and first part of small intestine. The majority of patients feel a bit anxious while preparing for a gastroscopy. This indicates the need for knowing the preparation and the very day expectations to ensure a peace of mind.
In this blog, we will talk about how to prepare for gastroscopy.
Why is an OGD Done?
The OGD procedure is done for certain reasons. Like:
Symptoms Investigation: Are you dealing with symptoms like chronic heartburn, consistent abdominal pain, or nausea? If so, a gastroscopy needs to be done. We perform this test to identify the probable causes behind the symptoms.
Diagnosing Conditions: In several cases, the tissue samples (biopsies) are taken during an upper endoscopy. This is used to diagnose diseases like gastritis, stomach ulcers, and coeliac disease. Well, this procedure also accounts for the early detection of stomach or esophageal cancers.
Finding Bleeding: The esophagogastroduodenoscopy is useful to identify the source of internal bleeding. This can be vomiting blood or black stools.
What are the Fasting Considerations Before a Gastroscopy?
Fasting is required before a gastroscopy to ensure an empty stomach. This allows the doctor to view the lining of your digestive tract.
Fasting leads to the prevention of vomiting risk and the risk of inhaling food or liquid into your lungs when you are put into sedation. Here is the fasting guideline for gastroscopy preparation.
Solid Food Deadline: You need to stop eating solid foods at least 6 to 8 hours before the procedure. It’s better if you don’t take any solid food items after midnight.
Liquid Guidelines: Stop consuming clear fluids (tea, black coffee, apple juice, etc.) at least 4 hours before the scheduled appointment time. Well, you can take small sips up to 2 hours but dairy-based liquids are strictly prohibited. Follow our gastroenterologist’s advice regarding this.
Things to Avoid: Chewing gums, mints, and hard candies are to be avoided on the day of the test as they stimulate saliva production and stomach acid. Remember, your stomach must be completely empty during the process.
What to Know About Medication Adjustment Before an Endoscopy?
You need to adjust your existing medicines before a gastroscopy. The probable adjustments are:
Blood Thinners and NSAIDs: Medications like Aspirin, Plavix, Warfarin or Ibuprofen must be stopped at least 5 days before the procedure. This is because such medicines increase bleeding risks when biopsies are taken.
Diabetes Management: Are you a diabetic patient? If so, insulin and oral digestive pills are to be skipped on the day of the test. The key reason behind this is that such medications lead to hypoglycemia (low blood sugar) and that affects the endoscopy procedure.
Weight Loss Medications: If you are on weight loss drugs (like Ozempic or Wegovy), you need to stop it at least a couple of weeks in advance. This helps to prevent complications with sedation.
Medication management is highly personalized. You need to consult our gastroenterologist before making any adjustment.
What Dietary and Lifestyle Changes are Considered Before a Gastroscopy?
Patients need to avoid high-fiber or hard-to-digest items for at least 2 to 3 days before the procedure because fiber is hard to digest and it takes longer to pass through the stomach. Like, you should not eat tough meats, raw vegetables, nuts, seeds, etc. Consider a low-fiber diet that includes white rice, bread, plain pasta, eggs, etc.
A light dinner is recommended on the day before the procedure. Avoid solid foods after midnight. You can consume liquids like apple juice, broth, and black tea up to 3 to 4 hours before the test. Avoid alcohol a day before the OGD procedure and smoking on the day of the procedure.
What Happens on the Day of Gastroscopy?
Here are the details you must know.
Day-of-Procedure Preparations
You need to wear loose and comfortable clothes on the day of gastroscopy. What you need to bring are A photo ID, insurance cards, and payment method/co-pay. We will send you a medical questionnaire a few days in advance. You need to complete this so that our doctor knows your health state and probable allergies.
Don’t bring any jewelry items with you when you come for a gastroscopy. You need to remove glasses, contact lenses, and dentures before the procedure starts.
Expectations During the Procedure
During the gastroscopy, you need to lie on your left side and your doctor wiill spray a local anesthetic to numb your throat. You will be given a sedation through your IV. This will enable drowsiness and you will not feel the pain.
The doctor will place a plastic mouthguard between your teeth. This is followed by guiding the endoscope down to obtain a clear view of the stomach. If required, tissue samples will be taken. The overall procedure lasts for 10 to 15 minutes.
Post-Procedure Recovery and Aftercare
After the procedure, you will be monitored for 1 to 2 hours to wear off sedation. Don’t drink alcohol, drive a car, and make any legal or financial decision in the next 24 hours. Start with small sips of water and soft foods after 2 hours of the endoscopy procedure.
Wrapping Up
Gastroscopy helps to diagnose gastritis, stomach ulcers, and coeliac disease. This is a quick procedure but you need to follow specific diet and medications. A good clinic ensures top-notch patient comfort.
Ready for a Gastroscopy?
We are a trusted gastroscopy clinic in Canada. Visit our clinic and interact with your experts. Get your gastroscopy scheduled.
Frequently Asked Questions (FAQs)
1. Will I Feel like I am Choking During Esophagogastroduodenoscopy?
This is a common fear among the patients but the answer is no. The endoscope is passed down your esophagus during the procedure but your trachea is left clear. Therefore, you can breathe normally through your nose and mouth. The sedation lowers your gag reflex and you will feel comfortable.
2. How Long do Biopsy Results take and How can I Obtain them?
At Scope MD, we provide the biopsy results within 2 to 14 days. For routine tissue samples (standard inflammation or infection checks), the biopsy report is offered within 2 to 5 days. If your sample requires specialized cultures, staining, or molecular testing, results might take 7 to 14 days.
3. I am Feeling Bloated after a Gastroscopy. Is it Normal?
In short, yes. Bloating is a common side effect of gastroscopy. Well, this stays for 24 to 48 hours. If it stays beyond that, you should refer to your gastroenterologist.
4. Can I Return to Work on the Same Day After a Gastroscopy?
No, you should not. You might feel perfectly alert after a couple of hours but the sedation medication stays in your system for up to 24 hours. Hence, your judgement, coordination, and reflexes are impaired. It’s better to not return to work on that day.
5. What if I have a Cold, Cough, or Fever on the Day of my Appointment?
If you have a mild cold with a runny nose, you can go ahead with the procedure. If you have a severe cold, a high fever, or difficulty breathing, you need to contact us immediately. A severe cough makes it difficult to adjust the endoscope safely.