Stevens-Johnson syndrome is generally considered to be a medication-induced condition. However, cases of non-drug-related SJS also occur, particularly related to hair dye containing paraphenylene diamine (PPD).
Even when hair dye is used properly, it can still cause toxicity, including skin damage and severe allergic reactions. Permanent hair dyes are most frequently associated with health risks because they contain a variety of strong chemicals, including ammonia, hydrogen peroxide, resorcinol, and PPD.
What is PPD?
PPD is a frequent component of permanent hair dye products and temporary henna tattoos, and exposure to it has been proven to cause severe facial edema, redness, sores, itching, burning, and contact dermatitis followed by erythema multiforme (EM) a form of SJS in sensitized patients. Other chemicals suspected to cause EM include bromofluorene, colophony, fragrances, epichlorohydrin, 1,2-ethanedithiole, and epoxy resin.
An allergic reaction to hair dye is an important health concern in connection with Stevens-Johnson syndrome because many people continue to use the dye in spite of an obvious allergy to it, putting them at risk for SJS. Although many hair dyes are marketed as non-allergenic or PPD-free, these products often contain cross-reactive chemicals such as toluene-2,5-diamine sulfate, which nearly 50 percent of those allergic to PPD are also allergic to.
Because of this cross-reactivity, dermatologists often recommend that patients allergic to PPD not use permanent hair dye, but patients are often unwilling to follow this advice and instead continue coloring their hair and tolerating the itching and rash that commonly follows. Although a patch test is typically required before applying hair dye, most people at home and in salons do not perform this test, believing that because no complication occurred during the last application, no adverse reaction will happen this time either.