Hi rose, thank you for all your valuable info. I have one more question. I have been noticing that alot of people who are getting shots of b12, that there level seem to be moving up rather slowely. I had blood drawn on 8/16/07 started taking the b12 sublingal the next day. (took them almost everday, may have missed a few) At that time my level was said to be 293 on 8/27/07 I was told my level went up to 346. This seems like a big jump. But I don't feel anybetter. Is it normal to have the number go up so quickly just by taking the sublingal?