Let me change part of what I wrote above:
There are not uncommon reactions to Vancomycin which might sound like an allergic reaction but are not. They are sometimes seen on the very first dose, which is not common for a true allergic reaction. It turns out that slowing the infusion may well allow the treatment to continue.
But I'll stick to the real advice: Infectious Disease folks understand these things, and will be the best source of help in a specific case.