Permanent-wave dermatitis: contact allergy to cysteamine hydrochloride.

Cysteamine hydrochloride (CHC) is a newly recognized sensitizer found in permanent-wave solutions. We report the case of a hairdresser who was found to be allergic to CHC. Our allergic patient was patch-tested to various chemicals found in permanent-wave solutions, including CHC (1.0% in petrolatum). Patch-test reactions were positive to CHC, glyceryl thioglycolate, diglyceryl thioglycolate, p-phenylenediamine (PPD), and PPD through a piece of latex glove. Sixty-four controls to CHC (1.0% in petrolatum) had negative results. Household-weight latex gloves were protective against CHC allergy. Persons with CHC-waved hair were not allergic. CHC contained in "neutral" permanent-wave preparations has been used in American beauty salons since 1993. We briefly discuss the introduction and significance of CHC in permanent waves.