pernicious anemia requires vitamin b12 injections for effective therapy. Anemia: Causes, Symptoms, Diagnosis, and Treatment Vitamin B12 - Well Nurse
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Sep 1995;53(3):211-2

Some people take sublinguals in addition to their injections....especially if they cant get frequent enough Injections from their doctors
Retrieved 25 February 2022

If you're genuinely B12-deficient, correcting it can dramatically improve fatigue, brain fog, and exercise tolerance

This step takes 30 seconds and prevents contamination that could ruin your entire vial

You do have to put in a little work of your own and try to be mindful of what you are eating
