A gastroscopy is a relatively simple procedure, to visualise the oesophagus, stomach and duodenum (first part of the small intestine). The main reason to perform this procedure is to investigate symptoms such as reflux, heartburn, upper abdominal pain and swallowing problems. A gastroscopy is usually performed with numbing throat spray and also under a light sedation with an anesthetist. Sometimes a biopsy is taken during the procedure.