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 12/21/2020
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A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
A doctor has provided 1 answer
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