A gastroscopy, also known as an upper endoscopy, makes the lining of the upper digestive tract visible. A flexible tube about as thick as a finger, the gastroscope, is advanced through the mouth and throat. At its tip are a light and a camera, and the images appear on a screen in real time. This allows the oesophagus, stomach and duodenum – the first section of the small intestine – to be examined closely.
Common reasons are persistent heartburn, pressure or pain in the upper abdomen, nausea or repeated vomiting. Difficulty swallowing, unintended weight loss or anaemia without an obvious cause are also reasons to take a closer look. The examination looks for inflammation of the oesophagus or stomach lining, for ulcers and narrowings – and for changes that are best detected as early as possible.
Helicobacter pylori is often also an issue. The bacterium can cause long-term inflammation of the stomach lining and favour ulcers; a rapid test on a tissue sample detects it. Before some procedures on the stomach, for example before treatments for severe obesity, a gastroscopy is also part of the preparation.
The examination is short, but inserting the instrument can trigger the gag reflex. An anaesthetic throat spray dampens it. Sedation can also be given, often called “twilight sleep”: a sleeping or sedative medication is given through a vein, and most people drift off for the duration of the examination. The guideline recommends offering sedation to everyone; simple gastroscopies can, however, also be done without it.