That would be called a late reaction- occurs several hours to days after exposure to the allergen. There are two other stages to an allergic reaction: 1st is Prodrome; it occurs within minutes to exposure to allergens The second one is; Early reaction occurs with minted to hours after exposure to allergen. I would recommend reading: The Complete Guide tomFood Allergies in Adults snd Children Scott H. Sicherer MD.

I second Cheryl’s answer!!

It may be a allergic reaction to soy lecithin and even though I am highly allergic to soy it didn't show up in skin test for it. Had to ask allergist to do blood test. It came up on that