Although NATURIGIN is based on 98 % organically derived ingredients, it still contains a few ingredients that can be related to hair dye allergy to maintain a permanent hair colour quality. No matter what product you are about to use it is always a good idea to perform the test 24 to 48 hours before to prevent potential adverse effects. How to do a patch test: 1.Use cotton swabs to dab a small amount of the product onto your skin in an innocuous place, for example behind your ear or at the nape of your neck. 2.Remember to do this with both the colour cream and activator, however, you do not have to mix the two just yet. 3.Wait 24 to 48 hours and check for a reaction to the two components. 4.If you see an irritation on the skin you should refrain from colouring your hair further. 5.If your skin has not reacted to the patch test you are all set to continue your hair colouring adventure and should not experience any allergic reactions.