Taking an oral product is very efficient, especially if on an empty stomach.
You can try stopping about 5 days before, but if you have been on it a long time, your levels will reflect that and not show a "low" if that was present before the supplement.
It is unlikely you will show a deficiency in the B12. You will probably test over 1000.
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Weezie looking at petunias 8.25.2017
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