Vitamin B12

Vitamin B12

This test is done to test how much B12 is in your blood.

This test is most often done when other blood test tests suggest a condition called megaloblastic anemia. Pernicious anemia is a form of megaloblastic anemia caused by poor vitamin B12 absorption. This can occur when the stomach makes less of the substance the body needs to properly absorb vitamin B12.

Your doctor may also order a Vitamin B12 test if you have certain nervous system symptoms. Low levels of B12 can cause numbness or tingling in the arms and legs, weak