Hello Smowball, In the salon where I work, there are several clients who have allergic reactions to hair dye's..our colourist has managed to avoid disaster by using foils to colour the hair.. then the colour stays just on the hair & in the foil 'package'. There are many different makes of colour these days ! She always does a patch test though...INSIST on this if you go to a salon!! as the dye will touch your scalp when its rinsed through..after its taken, but diluting it with the water may stop the problem.. I'm sorry I don't know many non salon colours ..Henna is a good one .. but has limited shades.. whatever you choose.. PATCH TEST.. hope this has been of some help! have a good weekend.. Mrs C x