The present invention relates to combinations of a proton pump inhibiting agent and at least one buffering agent that have been found to possess improved bioavailability, chemical stability, physical stability, dissolution profiles, disintegration times, as well as other improved pharmacokinetic, pharmacodynamic, chemical and/or physical properties. The present invention is directed to methods, kits, combinations, and compositions for treating, preventing or reducing the risk of developing a gastrointestinal disorder or disease including nocturnal acid breakthrough, or the symptoms associated therewith
