Omeprazole and Reflux Disease - Improvement of Clinical Outcome by Genotype-adjusted Dosing

Inclusion Criteria: * Patients with GERD grade A and B (mild to moderate severe disease) diagnosed by routine endoscopy will be recruited in different clinical and ambulant centres of gastroenterology; written informed consent is obligatory * Range of Age: 20-70 * BMI: 20-30 Exclusion Criteria: * Patients who are allergic to proton-pump inhibitors or show incompatibility * Patients who have lactase deficiency * Patients who have severe chronic disease * Patients who participated in another study during the last three months * Patients who are pregnant