Thank you for choosing DoctorSpring. Your B12 levels are 670 pmol/L which is well within normal limits. It is true that supplements will not case Vitamin B12 levels to a toxicity level, but it sure can increase the level from 300s to 600s. As long as it stays within normal limits and you do not have any symptom you need not worry.
Your CBC and LFT are normal. So there is no reason to be worried. If you take regular non vegetarian diet (assuming that you do not have significant medical illness) you can discontinue the supplement.
Hope this helps
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