I used to use semi-permamanet colours and never bothered with the allergy test and had no problems.
I've just switched to permanents and have been a good girl and tested every time. Trouble is I keep forgetting to do it and miss opportunities to colour, so my hair is looking greyer and greyer atm.
Does everyone play by the rules ? I know they're part covering the companies backs and part to pick up the rare bad reactions.
Have you ever had a reaction after being OK for ages?
Do I stop fretting and just get on with it????