Sodium lauryl sulfate-induced irritant contact dermatitis in vulvar and forearm skin of premenopausal and postmenopausal women

Abstract

Reactivity of the skin of the forearm and labia majora to three concentrations (2%, 3%, 5%) of sodium lauryl sulfate was studied in 20 healthy women, 10 premenopausal and 10 postmenopausal. Patches with the irritant were applied on day 0 for 24 hours. Skin changes were monitored by visual scoring and by the measurement of transepidermal water loss and capacitance as indicators of stratum corneum hydration on days 2, 3, 7, and 10. In forearm skin, irritant dermatitis developed in the majority of subjects as indicated by visual scoring and increase of transepidermal water loss. These changes were not significantly dependent on the concentration of sodium lauryl sulfate. In labia majora skin, irritant dermatitis developed in 50% of the women as determined by visual scoring; however, because of the pigmentation, visual scoring readings were less reliable in labia majora skin. Transepidermal water loss did not increase, but a significant and immediate decrease in capacitance was noted in labia majora skin. In forearm skin, postmenopausal women reacted less frequently and more slowly to sodium lauryl sulfate than premenopausal women whereas no age-related differences were observed in reaction of the vulvar skin. It is concluded that labia majora skin is not more reactive to sodium lauryl sulfate than forearm skin and that capacitance is more sensitive than transepidermal water loss in monitoring vulvar irritant dermatitis. Age-related differences in irritant reaction are apparent in the forearm, but not the vulva.