3 times I've had an allergic reaction over the last few months. My hands and face go bright red and itchy, it seems to happen after I take all my supplements at the same time. I usually take VitD3, K2, B12, Bcomplex, and more recently magnesium, selenium and zinc. I occasionally have a ferrous fumerate and powdered Vit c. I've just taken all of them together ( about an hour ago) and voila I've gone all red and itchy. I think it might be the Vit C, not sure, any clues?