Ginagirl
An allergy would need a protein for the body to react on, so no, not likely.
Automatic reaction; yes and no; when the
Iodine hit its rightful receptors, bromide has to leave. It make symptoms, stinks, tingle, is painful etc.
Then take more iodine, and the fluoride will start moving.
All this covered at the forum, how to make this process easier; salt, vit C etc.