The methyl form is less stable than cyano when it is removed from the multidose vial. It has to be protected from light, and heat once the vial is punctured.

This is one way to protect methylcobalamin injection sources:
http://products.minigrip.com/item/sp...bag/mguv3p0608

If you do decide to inject methylcobalamin, you'd need this type of storage for it. Perhaps a local compounding pharmacy would sell you some (an affordable small number) for your use.

You do have to consider WHO you purchase from:
http://www.fda.gov/Drugs/DrugSafety/ucm403346.htm

Hydroxocobalamin which may work for you, is available on RX and a pharmacy can order it for you.
So a doctor's prescription for this form can be ordered by any pharmacy for you.

Getting the DNA testing, will reveal if you can use the cyano, however, and save $$ in the long run and convenience. If you are not heterozygous, or homozygous for the MTHFR problem.

B12 is not really absorbed sublingually... as you discovered. But historically it has always been available and so the companies still make it. The B12 dissolves in the saliva and is swallowed to be then absorbed in the terminal ileum.

The doses are the same for all 3 types of injections.

So just be careful from whom you purchase your methylcobalamin injectable from.