I used to do 1cc every other day with B12...but my blood levels were low...I dont think you get more benefit out of it if you have what you need already, but I could be wrong...I still can get script inject B12 but for now use orals as I wanted to reduce pinning...but yea Im a big fan, and oh almost forgot since its been a few months, I also get B complex inject at doctors office typically every 2 weeks, and once a week or every other week an IV with B12, B complex, mega dosed vit C, and other anti oxidants, plus a bag of glutithione...
I totally believe in vitamin IVs and injects!!!