Abstract
Management of gastro-oesophageal reflux disease (GERD) is aimed at reducing oesophageal acid exposure to achieve symptom relief. Therapy has traditionally included advice to the patient on diet and lifestyle management. Recent evidence suggests, however, that some specific dietary modifications may be applicable to the Japanese patient. For example, ingestion of Japanese sweet cakes or rice cakes should be avoided by the Japanese patient with GERD as these foods may provoke heartburn. Pharmacological therapy is, however, usually also required for effective symptom relief. While antacids and histamine H(2)-receptor antagonists have a role in treating mild GERD, effective relief of many cases of oesophagitis is usually only achieved by using proton-pump inhibitors such as lansoprazole, omeprazole and rabeprazole. In the Japanese population, variation in the genetic polymorphism of CYP2C19 (a cytochrome P450 isoenzyme) leads to considerable inter-individual unpredictability in the activity of lansoprazole and omeprazole due to inter-individual differences in the extent to which these agents are metabolized. Consequently, rabeprazole, which does not undergo hepatic biotransformation by CYP2C19, offers significant advantages over the other PPIs as a result of its more predictable activity. This, coupled with its more rapid onset of action, leads to a more efficient and less variable acid-suppressing effect.