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Seattle, WA
A 33-year-old female asked:

Taking b12 supp for deficiency with symptoms of fatigue & lightheadedness. how long should i take them before expecting improvement and following up?

1 doctor answer2 doctors weighed in
Dr. Andrew Shiller
Physical Medicine and Rehabilitation 27 years experience
It depends....: are you taking it by pill? By injection? How much b12? Did they diagnose anemia? If so, what was your hemoglobin or hematocrit? Did they diagnose a low b12 level? What was it? Sorry for all the questions, but they're important for a clear answer. Many people feel great a few days after a b12 injection, but it depends on the circumstances. I hope you feel better soon!
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Last updated Nov 28, 2017


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