growing out highlights

My natural (haha) color is dark brown.  I have been dying it red for over a year.  Then I wanted to change, so I dyed (gasp) it black.  Then it looked really harsh against my ghost white skin, so I highlighted it. Since then, I've dyed my hair more natural auburn colors 3 times (one each month).  Nothing is taking to my hair (too porous) except that my roots are my natural dark brown color and the highlights have turned really bronzy red and they are about 3 inches down from my scalp.

How can I get these bright highlights OUT of my hair because they make my roots look darker.  I can't dye my roots for a while because my scalp is itchy. 

yes, i'm thinking about that a dark brown semi would take some of the red out.  Seems so easy when other people mention solutions, but sometimes I get stuck in a rut about what to do.

Thanks