Effect of omeprazole on H. pylori after two weeks of treatment.

The "clearing" effect of omeprazole 20 mg/daily on Helicobacter pylori (HP) was studied in 32 HP positive patients with duodenal ulcer (DU). Endoscopy and antral biopsies were made before and after two weeks of treatment with Omeprazole. HLO test and histology after Giemsa stain were used for the detection of HP. Fourteen of 28 (50%) initially HLO positive and 12 of 30 (40%) initially histological HP positive patients became HP negative. Nine of 23 (39%) patients, initially HP positive by both methods became HP negative. "Clearing" of HP in this particular group of patients did not have any influence on ulcer healing. It is concluded that omeprazole used for two weeks has a clearing effect on HP in a high enough percentage of patients with DU.