Hair dye contains a chemical known as paraphenylenediamine, or PPD, that is responsible for causing allergic reactions in some individuals. Reactions to this chemical in hair dye may manifest in different ways depending on the severity of the allergic reaction in the individual. Hair dye manufacturers recommend that individuals perform a skin test 48 hours prior to dying their hair to test for the presence of allergies.
Rash
Individuals who are allergic to hair dye my exhibit a reaction in the form of a red rash. According to Dr. Andrew Weil, the rash may appear anywhere the hair dye was applied or any area the hair dye touched. The rash may appear around the hairline, on the scalp or around the eyes and ears. Individuals who experience an allergic rash should contact a dermatologist or other health care provider for treatment recommendations.
Itching
Allergies to hair dye and the paraphenylenediamine it contains can cause the severe itching. The itching may be accompanied by a rash or other skin irritation. Anti-itch lotions and creams can be applied to relieve this symptom.
Swelling
Allergic reactions to hair dye can cause skin swelling; in some cases the swelling can be disfiguring for a short time. Swelling may need to be treated by a professional dermatologist with steroid creams and prescription oral steroid medications.
Skin Irritation
Peeling, redness and flaky skin are all symptoms of allergic reactions that may occur with the use of hair dyes. These irritations are likely to occur when the skin patch test is performed on allergic individuals.
