EFFECT OF 4 LANSOPRAZOLE DOSE LEVELS AND ONE DOSAGE REGIMEN OF OMEPRAZOLE ON 24-HOUR INTRAGASTRIC PH IN HEALTHY-SUBJECTS

Lansoprazole is a potent proton pump inhibitor and blocks gastric acid secretion. The potency of many antibiotics in eradicating Helicobacte r pylori may be considerably enhanced by increasing the intragastric p H due to a twice-daily coadministration of proton pump inhibitors. Thi s double-blind crossover study was designed to compare the effect on i ntragastric pH of four dose regimens of lansoprazole (30 mg o.a.d., 30 mg b.i.d., 45 mg b.i.d., 60 mg b.i.d.) after 5 days of treatment and to investigate whether an increment of lansoprazole dose level leads t o a more pronounced effect. Omeprazole 20 mg b.i.d. was administered a s a reference drug. The study was carried out in 20 healthy male subje cts. Intragastric pH was recorded by a nasogastric probe over 24 h. Al l dose regimens of lansoprazole were well tolerated and no unexpected drug-related adverse events were observed. The lowest lansoprazole dos e level 30 mg o.a.d., already increased intragastric pH considerably. This effect was even enhanced by increase of the lansoprazole dose as assessed by mean pH as well as percentage of time spent above differen t pH values. The increase in effect with lansoprazole dose increment f rom 30 mg b.i.d, to 60 mg b.i.d. was only very small. The time spent a t pH values above or equal to 3 after b.i.d. administration was slight ly higher with all lansoprazole dose levels compared to omeprazole. Th e time spent at intragastric pH values above or equal to 5 after b.i.d , oral administration of 30 mg, 45 mg and 60 mg lansoprazole was compa rable to that observed after b.i.d, oral administration of 20 mg omepr azole, so that it maybe recommended to use lansoprazole 30 mg b.i.d. a s a treatment equivalent to omeprazole 20 mg b.i.d. for eradication of Helicobacter pylori in combination with antibiotics.