Vitamin B₁₂ Deficiency

Vitamin deficiency related to inadequate intake or absorption of cobalamin (vitamin B₁₂)

Cobalamin is critical for central nervous system myelination and normal functioning.

Deficiency can cause ...

Asymptomatic patients may be diagnosed by the incidental finding of anemia or an elevated mean corpuscular volume (MCV) during routine testing or evaluat...

Parenteral cyanocobalamin replacement recommended in patients with severe neurologic symptoms: IM cyanocobalamin

• 1,000 μg/day for 7 days, then

• 1,000 μg weekly for 4 weeks, then

• 1,000 ...

Hematologic

• Reticulocytosis in 1 week

• Rise in hemoglobin beginning at 10 days; usually will return to normal in 6 to 8 weeks

• Monitor potassium in p...

E53.8 Deficiency of other specified B group vitamins

D51.0 Vitamin B12 defic anemia due to intrinsic factor deficiency

D51.3 Other dietary vitamin B12 deficiency anemia

D51.1 Vitamin B12 defic...

Vitamin B₁₂ deficiency can coexist with other anemia, thus, MCV can be normal, decreased, or increased.

For PA, cyanocobalamin must be lifelong.