Dear Linda C.
The vast majority of people are not allergic to the contrast dye used for MRI. If it happens that you are allergic, there are ready medications in the MRI suite that they will use to pervent any adverse outcome. If you have gastric problems there may be a problem with vitamin B 12 absorption This deficiency over a long period of time may induce a peripheral neuropathy.
Sincerely,
CCF Neuro MD