The patient with pernicious anemia is expected to need this treatment for the rest of life. Which is it?

• A. Iron supplements
• B. Vitamin B-12 injections
• C. Vitamin C supplements
• D. Folic acid tablets

Answer: (B)

Pernicious anemia is a deficiency of vitamin B12 due to loss of intrinsic factor, which is needed for B12 absorption in the small intestine. Because intrinsic factor is absent, B12 cannot be reliably absorbed from the gut, so replacement must bypass the gut—typically with vitamin B12 injections delivered on a lifelong schedule. This ensures ongoing B12 availability to support red blood cell production and nerve health.

Iron supplements would not fix B12 deficiency, since the problem isn’t iron. Vitamin C helps with iron absorption but won’t treat B12 deficiency either. Folic acid can improve the blood count temporarily, but it does not address the underlying B12 deficiency and can mask neurologic damage from B12 deficiency if given long-term. Therefore, regular vitamin B12 injections for life are the appropriate treatment.