1. What is a gastroscopy?
A gastroscopy, or upper GI endoscopy (called FOGD in French), is an examination of the upper digestive tract. A thin, flexible tube with a camera is passed through the mouth to look directly at the inside of the esophagus, the stomach and the duodenum (the first part of the small intestine). It is the reference test for the upper digestive tract.
2. Why does the doctor prescribe it?
Gastroscopy helps find the cause of many symptoms and allows biopsies (small tissue samples examined under the microscope). It is recommended in particular for:
- heartburn or reflux that persists despite treatment
- upper abdominal pain, repeated nausea or vomiting
- difficulty or discomfort when swallowing
- iron-deficiency anemia, or digestive bleeding (vomiting blood, black stools)
- unexplained weight loss
- testing for Helicobacter pylori, or follow-up of an ulcer, esophageal varices or a known lesion
3. How should I prepare?
- Fast: do not eat or smoke for the 6 hours before the test. For drinks, follow the exact instructions given when you book.
- Tell us about your medication, especially anticoagulants and antiplatelet drugs ("blood thinners"), as well as diabetes or allergies.
- Bring your prescriptions, recent blood tests and previous examination reports.
- If you have general anesthesia: an anesthesia consultation is planned beforehand, and someone must accompany you home.
4. How is the test performed?
Gastroscopy is done under local anesthesia (a throat spray) or general anesthesia for greater comfort. The test itself usually takes a few minutes. Air is blown in to unfold the walls, which may cause belching. Biopsies are painless. The endoscope is cleaned and disinfected between patients according to strict procedures.
5. What happens afterwards?
A sore throat or temporary bloating are common and pass quickly. You can drink and eat again as advised by the team. After general anesthesia, do not drive or make important decisions on the same day.
The doctor explains what was seen right after the test. If biopsies were taken, the results usually arrive within a few days and are discussed at a consultation.
6. Are there any risks?
Complications of gastroscopy are very rare: perforation, bleeding, heart or breathing problems, infection. After the test, seek medical help immediately if you have severe pain, fever, vomit blood or have black stools. To learn more, read our page on upper GI endoscopy.