Alteration in digestion and absorption of nutrients during profound acid suppression

Gastric acid suppression therapy has for many years been the cornerstone of the treatment of peptic disease. The availability of more potent inhibitors of gastric acid secretion and the increasing demand for maintenance therapy has renewed interest in the potential side-effects of profound and/or long-lasting therapy. This chapter focuses on the potential interference of gastric acid suppression therapy with the process of the digestion and absorption of nutrients. The theoretical mechanisms by which hypochlorhydria resulting from gastric acid suppression therapy may hamper digestion and absorption are multiple and well documented. Clinical studies evaluating the effect of gastric acid suppression therapy on the assimilation of nutrients are, on the other hand, scarce and have, moreover, yielded conflicting results. The reason for the latter may be related, at least in part, to elements of study design. Data indicating overt malabsorption or clear deficiencies in patients on long-term gastric acid suppression therapy are currently lacking. Nevertheless, it seems prudent, while awaiting the results of additional long-term studies, regularly to monitor these patients, especially those with increased nutrient demand, poor intake or suboptimal stores.