Hair colourant and scalp psoriasis

Hi - I'm a totally new member so apologies if there's been chats previously on this subject but am wondering if anyone has any advice/ experience similar please! I have monthly root colour applied (blond to disguise grey roots!). I also have worsening scalp psoriasis but vanity means I want to continue with the root coverage. Does anyone have any advice on any particular brand I should be using or avoiding so I can help my stylist make an informed choice, in addition to her own research on my behalf. Thanks