What about Sambucol? That's one thing I used a lot.
I used a lot of grapefruit seed extract, but recently discovered it is tainted with all kinds of icky chemicals(they don't lawfully have to put it on the label). So I think we will opt out of that one...
I am still trying to figure out what I can do for myself and my finicky allergy diet...other than taking my Allergy Multivitamin and some CLO and eating homemade plain yogurt every day. It's quite difficult to find ANY supplement not tainted with at least one of my allergens!