Effect of low‐dose rabeprazole and omeprazole on gastric acidity: results of a double blind, randomized, placebo‐controlled, three‐way crossover study in healthy subjects

BACKGROUND: The treatment of acid-related symptoms requires rapid and consistent acid suppression, especially with on-demand regimens. AIM: To compare the antisecretory activity of low-dose rabeprazole and omeprazole in healthy, Helicobacter pylori-negative subjects. METHODS: In this randomized, double-blind, placebo-controlled, three-way crossover study, 27 volunteers were given rabeprazole 10 mg, omeprazole 10 mg, or placebo once daily for 7 days with a 10-14-day washout between treatments. Intragastric pH was monitored for 24-h on days 1 and 7 of each treatment. RESULTS: Median gastric pH was significantly higher with rabeprazole than with omeprazole or placebo: day 1: 2.3, 1.4 and 1.3, respectively (P = 0.0056, rabeprazole vs. omeprazole; P < 0.0001, rabeprazole vs. placebo); day 7: 3.7, 2.2 and 1.3, respectively (P = 0.0016 rabeprazole vs. omeprazole; P < 0.0001, rabeprazole vs. placebo). Time with gastric pH above 4 was significantly higher with rabeprazole than with omeprazole: day 1, 5.8 h vs. 3.7 h, respectively (P < 0.02); day 7, 10.5 h vs. 4.6 h, respectively (P = 0.0008). CONCLUSIONS: Rabeprazole 10 mg provides more rapid acid inhibition compared with omeprazole 10 mg. After 7 days, the time with pH above 4 is more than doubled with rabeprazole 10 mg vs. omeprazole 10 mg.