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Treatment of vitamin B12 and folate deficiencies

Stanley L Schrier, MD
Section Editor
William C Mentzer, MD
Deputy Editor
Jennifer S Tirnauer, MD


This topic reviews the treatment of vitamin B12 and folate deficiencies, including the route and duration of therapy, monitoring, and expected hematologic and neurologic response.

Separate topic reviews discuss the clinical manifestations, diagnosis, causes, and pathophysiology of these deficiencies:

Clinical presentation and diagnosis – (See "Clinical manifestations and diagnosis of vitamin B12 and folate deficiency".)

Causes and pathophysiology – (See "Causes and pathophysiology of vitamin B12 and folate deficiencies".)


All individuals with documented vitamin B12 and/or folate deficiency should be treated, unless there is a strong reason not to do so (eg, palliative care setting or patient refusal). A number of general principles apply to both vitamin B12 and folate deficiency. These are outlined below and in a 2014 guideline on the diagnosis and treatment of vitamin B12 and folate deficiency from the British Committee for Standards in Haematology [1].

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Literature review current through: Nov 2017. | This topic last updated: Aug 09, 2017.
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