Reviv 3 Procare Prep Cleanser Shampoo Clinically Tested Hair And Scalp Care Anti Thinning Fine

Do you have to use in place of you regular shampoo?

Does this really make your hair feel thicker? Don't trust reviews listed as 1/2 are not verified purchases... Thanks!

Will this leave gray hair yellow?

Is this for hair loss? To help stop it? And to regrow hair?