This blog is to highlight the importance of patch testing when using any cosmetic – especially hair dye. Hair dye contains para-phenylenediamine (PPD), which a very small percentage of the population are allergic to and could result in anaphylactic shock. What is para-phenylenediamine (PPD)? – It is the chemical which makes the hair go darker. Or your arm when doing a patch test. You don’t need this much – about a 10p size.
People who have had black henna tattoos are especially vulnerable to the allergy but the allergy can happen to anyone at any time and even if you have been colouring your hair for 20 years. This is why patch testing every time you need or want to dye your hair is so important. Also keep an eye out for toulene 2,5 diamine in ingredient lists, this is in hair dyes for lighter colours and hair dyes which don’t contain PPD. It is just as potent as PPD and is a para dye. But always follow the instructions from the manufacturers or go to AllergyUK .
If in doubt – do a patch test.