Case Report

Effect of Omeprazole on Oral Iron Replacement in Patients with Iron Deficiency Anemia

Authors: Vivek R. Sharma, MD, Mark A. Brannon, BS, PA-C, Elizabeth A. Carloss, MD

Abstract

Hypochlorhydric states such as atrophic gastritis and partial gastrectomy have long been known to cause iron deficiency anemia. However, studies to date have failed to show a similar association with omeprazole, a proton pump inhibitor that also produces achlorhydria. These studies, however, have primarily involved nonanemic, iron-replete individuals. The effect of the drug has not been studied in patients with established iron deficiency, and to our knowledge the patients presented here are the first of their kind to be reported. Our observations support the probability that the profound hypochlorhydria induced by omeprazole may indeed impair the optimal absorption of orally administered iron in iron-deficient individuals, precluding them from obtaining therapeutically adequate amounts to establish the positive balance necessary for the resolution of anemia and the replenishment of stores. The possible explanations for this phenomenon are also discussed.


Key Points


* Several achlorhydric states are known to be associated with iron deficiency.


* Although proton pump inhibitors can cause profound achlorhydria, studies in iron-replete individuals have not shown a higher incidence of iron deficiency anemia.


* The cases presented suggest that omeprazole-induced achlorhydria may impair the response to oral iron therapy in patients with preexisting iron deficiency.

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References

1. Schmid A, Jakob E, Berg A, et al. Effect of physical exercise and vitamin C on absorption of ferric sodium citrate. Med Sci Sports Exerc 1996;28:1470–1473.
 
2. Massey AC. Microcytic anemia: differential diagnosis and management of iron deficiency anemia.Med Clin North Am 1992;76:549–566.
 
3. Conrad ME. Iron absorption, in Johnson LR (ed): Physiology of the Gastrointestinal Tract. New York, Raven Press, 1987, ed 2, pp 1437–1453.
 
4. Schade SG, Cohen RJ, Conrad ME. Effect of hydrochloric acid on iron absorption. N Engl J Med1968;279:672–674.
 
5. Hines JD, Hoffbrand AV, Mollin DL. The hematologic complications following partial gastrectomy: a study of 292 patients. Am J Med 1967;43:555–569.
 
6. Wheldon EJ, Venables CW, Johnston ID. Late metabolic sequelae of vagotomy and gastroenterostomy. Lancet 1970;1:437–440.
 
7. Stewart CA, Termanini B, Sutliff VE, et al. Iron absorption in patients with Zollinger-Ellison syndrome treated with long-term gastric acid antisecretory therapy. Aliment Pharmacol Ther 1998;12:83–98.
 
8. Bezwoda W, Charlton R, Bothwell T, et al. The importance of gastric hydrochloric acid in the absorption of nonheme food iron. J Lab Clin Med 1978;92:108–116.
 
9. Kaltwasser JP, Werner E, Schalk K, et al. Clinical trial on the effect of regular tea drinking on iron accumulation in genetic haemochromatosis. Gut 1998;43:699–704.
 
10. Golubov J, Flanagan P, Adams P. Inhibition of iron absorption by omeprazole in rat model. Dig Dis Sci 1991;36:405–408.