 [ Symptoms ] no allergy to shellfish ct scan wcontrast mild reaction of hives would there be allergic reaction to shell fish now [ Disease ] you absolutely can be allergic to iodine true that most people who are allergic to seafood are allergic to the proteins within but some people as myself have a true reaction to high levels of iodine and it can buildup to a reaction by consuming iodine rich foods consecutively yes we need a small amt of iodine for our thyroid to work but people with a true allergy to iodine have to take in the bare minimum and live with daily itching