Wondering if it is safe to use over the counter hair color over top of professional hair color. Been going to salon for years and would like to try it myself

I would advise letting your hair grow out before putting a different chemical on top of another chemical. Hairdressers usually do a better job than we can do ourselves.

I dye my hair myself all the time. I have done it over highlights and professional color. My hair always looks great and it makes it so shiny. I use Loreal - it used to be called Casting, but I think it is something else now. It works great.