Some issues won't go away and sensitivity to permanent hair colour is one of them. In fact sensitivity to colour is increasing for lots of reasons.
Are you aware that all permanent hair colour and some semi and quasi colour contain the chemicals PPD or PTD, regardless of the brand you use, and also that sensitivity can change any time?

Thankfully, technology has moved on, and now you can use a patch test called 'Colourstart' to screen for sensitivity scientifically, cleanly and conveniently. 
It is a unique patch test used by hairdressers as a skin allergy test in more than half of the UK's leading salons!

The purchase price is per allergy patch.

Now you can use this simple test kit safely at home !