A comparative study of intragastric acidity during post-breakfast and pre-dinner administration of low-dose proton pump inhibitors: a randomized three-way crossover study.

Author(s): Miki M, Adachi K, Azumi T, Koshino K, Furuta K, Kinoshita Y

Affiliation(s): Department of Gastroenterology and Hepatology, Shimane University, School of Medicine, Shimane, Japan.

Publication date & source: 2006-11-15, Aliment Pharmacol Ther., 24(10):1445-51. Epub 2006 Oct 10.

Publication type:

Background The absorption and bioavailability of proton pump inhibitors is influenced by food intake. Proton pump inhibitors bind to the parietal cell active proton pump, which is maximally stimulated after dinner: usually the largest meal of the day. However, it has not been fully clarified whether the efficacy of proton pump inhibitors differs between post-breakfast and pre-dinner dosing. Aim To perform a pH-monitoring study to clarify this issue for two low-dose proton pump inhibitors. Subjects and methods The subjects were 20 healthy male volunteers (seven Helicobacter pylori-positive and 13 H. pylori-negative), who were divided into two groups of 10 and administered 15 mg lansoprazole or 10 mg rabeprazole, respectively. All subjects underwent ambulatory intragastric 24-h pH- monitoring under three conditions allocated randomly: (i) without medication, (ii) seventh day of post-breakfast administration and (iii) eighth day of pre-dinner administration of each drug. Results There was no significant difference in the percentage time during which pH >/=4.0 in the 24-h period between post-breakfast and pre-dinner administration of both drugs (56.6% vs. 55.8%; P = 0.557), although intragastric acidity during administration of both drugs was significantly lower than that without medication. Conclusions The timing of drug administration does not significantly influence the efficacy of low-dose proton pump inhibitors.