I've been using Boots henna and horsechestnut shampoo and conditioner for some time and am now wanting to dye my hair a permenant colour. Can I do this safely as I've read that you shouldn't use a chemical dye (like Loreal Feria) after dying your hair with henna. Is the same true if you've used a shampoo containing henna?
I've been using Boots henna and horsechestnut shampoo and conditioner for some time and am now wanting to dye my hair a permenant colour. Can I do this safely as I've read that you shouldn't use a chemical dye (like Loreal Feria) after dying your hair with henna. Is the same true if you've used a shampoo containing henna?

Edit: The shampoo states that it enhances the colour and shine of red and brown hair

Has this shampoo actually changed the color of your hair?
If it has, use another shampoo and conditioner until your hair grows out. (Unless of course you don't mind
very short hair in places where it might break off.)
To be safe, if you are set in dying back your hair, contact the shampoo company with the number on the bottle, and ask them.
(A semi six week color such as loving care should not harm your hair.)

The amount of Henna in shampoo is probably negligible. It's not the same as using Henna as a colourant.