[Management of gastroesophageal reflux disease (GERD) with refractory to standard dose of proton pump inhibitor].

Approximately 10% of Japanese patients with reflux esophagitis (RE) are refractory to a standard dose of proton pump inhibitor(PPI) and most refractory patients have severe RE. Lack of response may be due to inadequate gastric acid suppression in conjunction with CYP2C19 genotype status and nocturnal acid reflux. Twice-daily dosing of PPI for inadequate gastric acid suppression and the administration of H2-receptor antagonist before bedtime for nocturnal acid reflux, is effective in most cases. The response to a standard dose of PPI in patients with non-erosive reflux disease (NERD) is approximately 50%. The reasons for a lower response rate, compared with RE patients, are not clear but may relate to an acid-hypersensitive esophagus, inadequate gastric acid suppression, non -acid reflux and emotional or psychological abnormality. High dose PPI therapy, endoscopic or surgical anti-reflux therapy, or/and pain modulators may be effective in some patients.