We quite often get asked at Passion Hair and Beauty why patch tests are so important.  So thought it would be good to explain a little more about the benefits, the risks and process.


The NHS website (https://www.nhs.uk/conditions/hair-dye-reactions/) states that many hair dyes (and beauty products) contain ingredients that can irritate your skin or cause an allergic reaction. It’s important to be aware of this risk, and know what to do.  Reactions to hair dye (and beauty products) are avoidable if you follow some simple safety advice.

Some people are prone to a skin reaction called contact dermatitis.  This means their skin becomes red, dry and irritated (inflamed) when they come into contact with a particular substance.  The substance may either be an irritant, or an allergen, triggering an allergic reaction that affects the skin.  Many permanent and some semi-permanent hair dyes contain a chemical called paraphenylenediamine (PPD) –  a known irritant and allergen. This is the culprit of most reactions to hair dye.


Patch and skin allergy tests (also known as Colour Safety Tests in the hair industry) usually involve putting a small amount of the products behind your ear or on the inside of your elbow/forearm.

Mosts test skin allergy tests require 24 hours for beauty treatments and 48 hours for heir treatments.

Tests have to be repeated on a regular basis (normally six months) or if there are significant changes, such as being pregnant or the start of certain medication.  All tests will be recorded on your client record card so that we are able to see when your next test is due.