I use the Dye-free Children's Benadryl. It's ingredients are: carboxymethylcellulose sodium, citric acid, flavors, glycerin, purified water, saccharin sodium, sodium benzoate, sodium citrate, and sorbitol solution. I have a corn (and other) intolerant 3 yo and I use it for her. She's not anaphylactic though, so I don't know if it contains part corn. I know that it doesn't make her intolerances worse, and can often make them better (especially with corn, when she gets eczema). I would call the company about the corn, if it were an anaphyactic situation.
Kathy, mother of 3, wife of 1. My new recipe blog: www.kathysrecipebox.wordpress.com (no longer searchable by allergen, but at least it doesn't have a virus!)