CYP2C19 Genotype as a Predictor of Gastric Acid Suppression and Healing of Erosive Esophagitis

Proton pump inhibitors are metabolized through the CYP2C19 hepatic enzyme system. Several variant genotypes of this enzyme exist which may lead to decreased, normal or increased metabolism of the proton pump inhibitor. With alteration of metabolism, the degree of gastric acid suppression achieved and efficacy in treating reflux could be affected. For example, Asian populations who have low activity of CYP2C19, commonly need lower doses of proton pump inhibitors to manage gastroesophageal reflux because of more sustained blood levels and availability of the drug. Theoretically, those patients who are rapid metabolizers would receive less effective treatment with proton pump inhibitors