Percutaneous endoscopic gastrostomy (PEG) is reported to be a safe method for enteral feeding, although its ability to prevent gastro-oesophageal reflux (GOR) during enteral feeding remains controversial. In 12 elderly patients fed enterally to avoid the risk of tracheal aspiration, we have compared two 24-h oesophageal pH profiles, one recorded when enteral feeding was delivered at first via a nasogastric tube (NGT), and the other via a PEG. The second recording was always performed at least 8 days after gastrostomy placement. Enteral nutrition consisted of 500 ml of a polymeric diet delivered 3 times a day at 08:00, 13:00 and 18:00. After gastrostomy placement, enteral feeding was associated with a pathological acid reflux in 8 out of 12 patients. In all of these 8 patients, GOR was mostly related to a high number of reflux episodes. In 4 out of 8 patients, GOR occurred only during the 3 h following the administration of the nutritive diet. In 4 of the patients, GOR did not occur any more after removal of the NGT, whilst gastrostomy placement was followed by GOR in 5 patients. GOR during enteral feeding via PEG is common in elderly subjects. We have shown that a chronological relationship existed in some patients between the endoscopic procedure and the onset of a pathological GOR.