When someone has an allergy to hair dye، they are most likely allergic to one of the chemicals in the dye rather than the entire product. The most common cause of these allergic reactions is para-phenylenediamine، also called PPD. PPD is found in most commercially produced hair dyes. The PPD is usually mixed with peroxide in the dye to alter the hair color. What happens before this reaction is fully complete also makes the PPD more likely to interact with the skin and cause an allergic reaction.
PPD can be found in commercial hair dyes under many alternative names. These include names such as PPDA، 1،4-Benzenediamine، and Phenylenediamine base.
Another common chemical found in hair dye is para-toluenediamine (PTD)، which can be tolerated better than PPD but may still cause an allergic reaction in many people.
Allergic contact dermatitis is a reaction caused by the skin being touched by something it is allergic to. Once sensitized، the affected skin will usually become inflamed and red when exposed to the offending allergen.Medics Today said.
The scalp، ears، beard، or neck may become red and inflamed. The eyes also may itch، and the eyelids may swell as the reaction develops.
Most contact dermatitis from a hair dye allergy is classified as type 4 hypersensitivity، and it usually takes hours or more for symptoms to occur upon exposure.
Hives may also show up after a hair dye application. The symptoms of these are red، raised، and itchy patches on the body. Someone may experience difficulty swallowing and respiratory problems، such as wheezing and sneezing.
Anaphylactic shock It is also possible، but far less common، for someone to have an immediate، anaphylactic allergic reaction or type 1 hypersensitivity to hair dye، leading up to anaphylactic shock.
Symptoms may include hives، swelling of the face and airways، shortness of breath، and a drop in blood pressure with a fast heart rate and possibly loss of consciousness. Anaphylactic shock can be fatal، and anyone experiencing these symptoms needs immediate medical attention.
Diagnosis One of the difficulties in identifying a reaction to PPD is that symptoms typically will not show up until after the second usage of the product.
The body becomes allergically sensitized to an invading substance the first time it is used. Once it is applied a second time، reactions will often start to appear. Reactions may also get worse with more applications of the product.