it's probably not so much the shampoo as it is the water that's affecting your hair color. i have actually inquired from a lot of different companies and most of the shampoos; if you look at head & shoulders for example does not affect your hair color. so that's something that's very important to understand. but what happens is when you color your hair the hair can become more porous and that means that everything you do to your hair can affect it more. so sun exposure will make your hair more brassy and more dry. because the sun also dries out your skin and takes the water out of your skin and your hair as well as well as the ultraviolet rays changing the color. so that's something you want to be careful about. don't stay in the shower for too long and don't let the water just run over your hair for more than ten minutes at a time. use a conditioner and a shampoo that are specifically designed for color treated hair because they will coat the hair and give it some strength and volume and help protect that color from fading over time. but it's more the water than the shampoo that's the culprit.
i think my shampoo is stripping my hair color. is there something in shampoo that's wrecking my hair color?