[Dose-response effect of lansoprazole in patients with Zollinger-Ellison syndrome]

Lansoprazole, a new substituted benzimidazole, is an effective acid proton pump inhibitor acting by inhibiting selectively H+/K+ ATPase of the gastric parietal cell. This study was performed to assess the effect of successive 30, 60, 90 and 120 mg dosages of lansoprazole in 4 patients suffering from Zollinger-Ellison syndrome. The basal gastric acid output was markedly inhibited in comparison with baseline values (mean maximal reduction: 87%; extremes: 75-99%) and was dose-related. Lansoprazole inhibited pepsin output globally with a dose range effect between 30 and 90 mg/day. The treatment induced a rapid relief of clinical symptoms. No biological abnormality was noted. These data proved that lansoprazole is efficient for treating gastric acid hypersecretion in patients suffering from ZES.