Reactions to Treatment with Vitamin

Positive intradermal skin tests using pure vitamin B12 were seen in 2 out of 1000 individuals tested, although they did not react to an intramuscular injection (B23). 

In addition to its use in relieving a deficiency state and certain metabolic abnormalities, vitamin B12 has also been used as a tonic and untoward reactions have been exceedingly rare. 

Anonymous, Nomenclature policy Generic descriptors and trivial names for vitamins and related compounds. /. Nutr. 106, 8-14 (1976). 

and Mehlman, C. S., Isolation of gastric vitamin B12 binding proteins using affinity chromatography. I. Purification and properties of human intrinsic factor. /. Biol. Chem. 248, 3660-3669 (1973). 

Areekul, S., Jaroonvesama, N., Charoenlarp, K., Kasemsuth, R., and Cheeramakara, C., Serum vitamin B12 and folic acid levels in patients with Fasciolopsiasis. Southeast Asian J. Trap. Med. Public Health 10, 67-72 (1979). 

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