Oral Treatment of Pernicious Anemia with Vitamin B12without Intrinsic Factor

THE absorption of ordinary amounts of vitamin B12 from the gastrointestinal tract is normally dependent on the presence of the intrinsic factor of Castle in the gastric secretions. A lack of intrinsic factor results in deficient absorption of vitamin B12 and the clinical picture of pernicious anemia. In the treatment of this condition it has been necessary either to administer vitamin B12 parenterally or to add intrinsic factor to the vitamin B12 given by mouth to ensure proper absorption. If, however, the oral dose of vitamin B12 is increased to more than 1 mg. enough . . .