It is important to understand that doctors will tell you "normal" when you are in the dangerous lower ranges. The labs have not updated their tests. So get the actual numerical result.

Also high readings while taking supplements are not dangerous and will be out of range that way too. Doctors tend to react to anything out of range, but in this case having high B12 actually helps.

More information on my B12 thread. It has a medical link, from 2003 explaining oral supplements and the new cut off of 400. The link there is from the American Association of Family Physicians. It is written for doctors, but is easily understandable for others too.

http://neurotalk.psychcentral.com/thread85103.html

B12 levels need to be high in the blood so that the B12 can move into the spinal cord and brain. Higher levels push this factor. Some studies have been done on MS and fibro patients, and found both have very low B12 in the cerebrospinal fluid.
However, not many studies have been done in total on this aspect. Methylcobalamin has to be in the brain in order for you to make melatonin.

You can use oral (sublinguals as oral) successfully. Just remember to take them on an empty stomach. iherb.com, Swanson's, and Puritan's pride online all have methylcobalamin at very affordable prices.