I'm not sure what I'm exactly allergic to, but I'm also allergic to the Henna Tattoo ink. What hair dye brand can I use so that I don't get an allergic reaction?

If you're also allergic to henna, the choices become more limited, but try doing a search on "vegetable hair dye" or "natural hair dye" and see what you can find. All the brands I know of are henna based :(