Originally Posted by mrsD

Yes, pabb is correct. B12 is not the only thing you need.

I hope you are using methyl form and not cyano for the B12.

Typically in an alcoholic, there are other things low as well.
The usual treatment involves the whole Bcomplex, and high dose thiamine. Another nutrient lost with heavy alcohol use is magnesium.

I would make sure you are taking a B-50mg complex, 300mg of thiamine in divided doses or the newer benfotiamine, and a quality magnesium supplement:
Do not choose magnesium oxide, which is not absorbed.

People who consume high amounts of alcohol and/or caffeine during the day lose magnesium thru the urine.

If you were an alcoholic and not eating properly, you may be low in nutrients, like protein, and essential fatty acids. So those have to be provided for your nervous system and bones.