Use the color remover - prell and Color Oops (walgreens / cvs). READ ON!
HI there - I read a string including the (thank you) amazingly helpful comments from PrettyLady and I AM SO FREAKING PLEASED! I had my stylist dye my hair, top needed to match bottom from a home kit I put on. I'm naturally med dk to dk brn. I have lightened & colored - both in salon and at home. My roots were BRIGHT orange (stylist had a whoops moment) 2 "dyes" ago and I was just about Elvira Jet Black after this last pass of color. Searched these forums in desperation and heeded PrettyLady's & others comments.
I went and bought both Prell (original formula - green in a clear plastic bottle) and the OOPS color remover - $15 or less for both. OH and a good conditioner. I put the Prell on dry hair and sat for 45 minutes. Played on computer. Washed it out, conditioned, dried hair. Note: some color ran off in the tub but when I dried - 1/25th of a change - maybe. So I put on the Color Oops not having high hopes. I have really thick, long dark hair that's been bleached, colored, beaten with a stick, etc etc and thought "this'll probably dry my hair like straw, leave the ends black and the roots will go back to the bright orange,"(because the box says if you had bleach it'll take you back to natural OR the lsat bleaching you killed your hair with), but I figured "I'll just go pay more to get it fixed" ...and put it on.
HOLY MOSES PEOPLE! I am SHOCKED! As one reviewer noted, you won't see color wash down the drain, and it won't look THAT different before you dry. But when you do - halleluya (however you spell it)! ALL the black is gone, the ends are a nice med to dk brown with a slight copper highlight and the roots are ...the same! Voila! And when I say a light copper that's what I mean because red doesn't look good on me and I do not like it (on my head anyway). So basically I just went from black with burgundy / bordeaux / purply highlights to a med to dk brown with the slightest copper highlights. I love it.
I do not know if the Color OOPS (extra strength) would have done this alone, if it did or if the 45 minute "Prell soak" helped it but if you're in my position - do both like I did and condition well. Apparently besides stripping out a little color, Prell strips out all product buildup. My hair hasn't had this much shine & body in forever. Best of luck to all and I hope this helps someone with similar conditions.