Allergic reactions to mb12 shots or nasal spray?

[Guest guest]

I'd like to have my sons do a B12 shot but I'm worried about an

allergic reaction. One is recovering now from an allergic reaction to

a penicillin-based oral antibiotic and is covered with a red splotchy

rash. The b12 should help that but I'm concerned about what else is in

the shot. I will ask the pharmacist but not sure I'll know what the

stuff is... anybody have ideas what is likely? Or what I should be

looking for?

I've written our compounding pharmacy here (Costa Rica) about making

up the B12 nasal spray, she will do it with folic acid instead of

folinic acid. Will this make a difference? She seems to think not.

Also, what are the likely other ingredients in the nasal spray?

Thank you,

Sally