Digestive Diseases and Sciences

, Volume 25, Issue 3, pp 188–192

Malabsorption of protein-bound cobalamin but not unbound cobalamin during cimetidine administration

  • William M. Steinberg
  • Charles E. King
  • Phillip P. Toskes
Original Articles

DOI: 10.1007/BF01308137

Cite this article as:
Steinberg, W.M., King, C.E. & Toskes, P.P. Digest Dis Sci (1980) 25: 188. doi:10.1007/BF01308137

Abstract

The suppressive effects of cimetidine on acid, pepsin, and intrinsic factor secretion have been well documented; however, the effect of cimetidine on cobalamin absorption has not been assessed. The absorption of both unbound [57Co] cyanocobalamin and protein-bound [57Co] cyanocobalamin was evaluated in 12 patients with duodenal ulcer disease during and after discontinuation of cimetidine therapy. Cimetidine administration did not lead to malabsorption of unbounds cobalamin but caused malabsorption of protein-bound cobalamin (0.22±0.08%, [mean±1sem] versus 2.3±0.10% in control subjects,P<0.01). This malabsorption was reversible upon discontinuation of cimetidine. Patients on cimetidine therapy malabsorb protein-bound cobalamin and, during long-term treatment, are at risk for developing cobalamin deficiency. This malabsorption of protein-bound cobalamin is not detectable by the usual tests of cobalamin absorption which employ unbound cobalamin.

Copyright information

© Digestive Disease Systems. Inc 1980

Authors and Affiliations

  • William M. Steinberg
    • 1
  • Charles E. King
    • 1
  • Phillip P. Toskes
    • 1
  1. 1.Department of MedicineGainesville Veterans Administration Medical Center, and University of Florida College of MedicineGainesville
  2. 2.Gastroentorology SectionVeterans Administration Medical CenterGainesville