Acid inhibitory characteristics of omeprazole in man.

Single-dose studies in man have shown that omeprazole is a potent inhibitor of acid secretion stimulated by betazole, pentagastrin, modified sham-feeding and peptone. The degree of inhibition is dose-dependent and correlates to the area under the plasma omeprazole concentration-time curve. The duration of action of a single oral dose is 2-3 days and not dependent on a sustained plasma concentration of omeprazole. During repeated once-daily administration the level of acid inhibition increases over the first 5 days, after which it stabilises. With once-daily omeprazole treatment it is possible to almost abolish 24-hour intragastric acidity in the majority of DU patients.