To prepare for a gastroscopy you’ll need to fast from food for at least 6–8 hours (you can drink water up to 4 hours before your gastroscopy).
Your stomach needs to be empty to enable your doctor to see your gastric mucosa and reduce the likelihood of vomiting, which could cause pneumonia.
Your doctor will give you specific instructions to prepare. You should follow these instructions strictly, otherwise your doctor may have to delay or repeat your procedure.
Check with your doctor if you should take your normal medications before the procedure.