A 37-year-old member asked:
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how long does it take a vitamin b12 injection to take effect?

1 doctor answer
Dr. Joel Gallant
35 years experience Infectious Disease
Take effect?: I'm not sure what you mean by 'take effect.' the only indication for vitamin B12 injection is for people with severe B12 deficiency or those who are unable to absorb B12 from their diet. That applies to very few people. If you're being given B12 injections for 'energy, ' you should be aware that's it's a commonly administered placebo.
Answered on Oct 29, 2018

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Related questions:

A 62-year-old male asked:
Dr. Thomas Namey
47 years experience Rheumatology
Inject first!: I have all my patients on sublingual b12, 2500mcg when needed. However, i give them a three mg injection first. Routine B12 injections can be virtual ... Read More
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A 39-year-old member asked:
Dr. Yash Khanna
56 years experience Family Medicine
2to3 days: It is a water soluble vitamin and gets excreted by kidney and if not needed in body it is excreted within 2to3 days.
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A 46-year-old member asked:
Dr. You Sung Sang
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Usually 1 month: For severe deficiency, initially the shots may be daily/weekly. Once levels stable, they are usually given im monthly.
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A 19-year-old female asked:
Dr. Robert Wilson
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Injections: Most people get plenty of B-12 from their diet. A few with pernicious anemia lack a factor that helps absorb B 12 and require injections to get the vi ... Read More
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