At some point, I feel if you are taking B12, you need to add in the other B vitamins. Depending on what your levels are, you can either approach it by introducing single vitamins one at time to see how you react or take a good B complex. Which ever route you choose, I prefer the more bio-available B vitamins just in case you have the some level of the MTHFR genetic mutation. You can read more about that on http://mthfr.net