Incidence of human skin sensitization to isostearyl alcohol in two separate groups of panelists.

Human repeated insult patch testing with an experimental pump spray antiperspirant formulation elicited sensitization reactions in two separate groups of panelists. After several rechallenges with variations of the formula components, isostearyl alcohol at 5% concentration in the product emerged as the causative agent in both groups. Due to the high content of alcohol in the pump spray antiperspirant, control patch testing was done with 100% ethanol, which served as the vehicle for testing isostearyl alcohol alone. All reactions were negative. Six out of 148 participants in the first group and one of 60 in the second group exhibited sensitization responses to isostearyl alcohol.