Fast Five Quiz: Vitamin B12 Deficiency Key Aspects

Romesh Khardori, MD, PhD


January 17, 2023

Oral and intranasal routes are not indicated for treatment of pernicious anemia until symptoms resolve, no signs of nervous system involvement remain, and the patient achieves hematologic remission. Before that time, intramuscular and subcutaneous routes are used. Holding treatment for vitamin B12 deficiency to test for polycythemia vera is not necessary; treatment for vitamin B12 deficiency may uncover the issue. Patients who exhibit hematologic or clinical responses consistent with polycythemia vera should be evaluated further.

Learn more about vitamin B12.

This Fast Five Quiz was excerpted and adapted from the Medscape articles Vitamin B12 Associated Neurological Diseases, Pernicious Anemia, and Cyanocobalamin.

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