vitamin b12 injection hives induced acneiform eruption Difference Between Rash and Hives?

Its potent

As with all research compounds, investigators should implement appropriate laboratory safety protocols and follow institutional guidelines for handling investigational chemical compounds in controlled research environments

These are the things that should make you cancel the appointment, forfeit the deposit if you have to, and leave

Even the National Institutes of Health website will tell you there is no toxicity to B12

Asymptomatic : In asymptomatic patients with risk factors (see Table 1: Patient Risk Factors Associated with B 12 Deficiency above) consider supplementation in lieu of testing

The right choice, however, comes down to one critical factor: absorption