What kind of shampoo can I use for dry scalp thats safe on colored hair?!?

I don't know what to do, I have really dry scalp and it flakes and itches, and then it scabs over and its so gross. The problem is I can't use dandruff shampoo like head %26amp; shoulders etc. because I highlight my hair and it will ruin the color and my regular color safe shampoo doesnt do anything for the dryness. What can I use??What kind of shampoo can I use for dry scalp thats safe on colored hair?!?
I don't know why Head and Shoulders ruins your color. Cause that's what I was using when I was highlighting my hair.