Can i take vitamin b12 with my medication ?

What medication?: You haven't supplied any info about the medication you're talking about. Although the risk to your health would be low, it's hard to answer correctly without that info. Some meds shouldn't be combined with B12 for absorption reasons, etc. If you want us to try again, re-ask and include the medication you're wondering about.

Yes, however...: You don't say which medication but it is safe to take B12 with all medications, but it should not be taken at the same time as tetracycline (take at least an hour apart). Many medications reduce absorption & thus increase our need for B12. I advise sublingual or chewable methylcobalamin. See http://umm.edu/health/medical/altmed/supplement/vitamin-b12-cobalamin & http://bit.ly/1cBhjvn.