Steinberg W M, King C E, Toskes P P
Dig Dis Sci. 1980 Mar;25(3):188-91. doi: 10.1007/BF01308137.
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 unbound cobalamin but caused malabsorption of protein-bound cobalamin (0.22 +/- 0.08%, [mean +/- 1 SEM] versus 2.3 +/- 0.10% in control subjects, P less than 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 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.
西咪替丁对胃酸、胃蛋白酶和内因子分泌的抑制作用已有充分记录；然而，西咪替丁对钴胺素吸收的影响尚未得到评估。在12例十二指肠溃疡病患者中，于西咪替丁治疗期间及停药后，对未结合的[57Co]氰钴胺素和蛋白质结合的[57Co]氰钴胺素的吸收情况进行了评估。给予西咪替丁并未导致未结合钴胺素的吸收不良，但导致了蛋白质结合钴胺素的吸收不良（0.22±0.08%，[均值±1标准误]，而对照组为2.3±0.10%，P<0.01）。停用西咪替丁后，这种吸收不良是可逆的。接受西咪替丁治疗的患者会出现蛋白质结合钴胺素吸收不良，长期治疗期间有发生钴胺素缺乏的风险。停用西咪替丁后，这种吸收不良是可逆的。接受西咪替丁治疗的患者会出现蛋白质结合钴胺素吸收不良，长期治疗期间有发生钴胺素缺乏的风险。通过使用未结合钴胺素的常规钴胺素吸收试验无法检测到这种蛋白质结合钴胺素的吸收不良。
