LAHORE: 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. Fast facts on hair dye allergy: The most common symptom of a hair dye allergy is contact dermatitis. A quick reaction to the first signs of a hair dye allergy can make all the difference. Gentle moisturizers may help relieve symptoms of dry or itchy skin. PPD may be the most common cause of allergic reactions to hair dye. 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. 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. 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. 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. Non-allergic contact dermatitis may affect people who are not allergic to hair dye. It is also possible for people who are not allergic to hair dye to react when using it, leading to non-allergic contact dermatitis or other symptoms. Some skin types are more sensitive to chemicals, including PPD. This type of reaction may be more common when someone switches brands with different dye formulations. Most people will find that their skin may become dry, stretched, or cracked. The scalp may tighten or feel as if it is burning. Symptoms of irritation will usually appear within 48 hours. At the same time, many people with a hair dye intolerance may have an almost immediate reaction to PPD or other hair dye components. If any symptoms of a hair dye allergy show up, the hair should be washed immediately. The excess dye can be removed through multiple gentle washes with a mild soap and plenty of rinses with clean water. It may also help to rinse the hair with a solution of 2 percent hydrogen peroxide after washing the excess out. This helps to oxidize the PPD fully and make it non-reactive. This step has mixed results, and it should be avoided if it makes symptoms worse. Creams with alcohol or certain other chemicals may irritate the skin. Natural creams or simple wet compresses of olive oil and lime may help. Steroid creams may be used to reduce inflammation with swelling and irritation in cases of stronger allergic reactions. Some over-the-counter steroid creams may work well enough to manage symptoms if they are less severe. However, more severe allergic reactions may require a prescription steroid cream or possibly oral steroid therapy. Published in Daily Times, January 8th 2018.