RESUMO
BACKGROUND: Ingredients of leave-on cosmetics and body care products may sensitize. However, not every case of cosmetic intolerance is due to contact sensitization. OBJECTIVE: To describe the frequency of contact sensitization due to cosmetics in a large clinic population, and a possible particular allergen pattern. METHODS: Retrospective analysis of data from the Information Network of Departments of Dermatology, 2006-2011. RESULTS: Of 69 487 patients tested, 'cosmetics, creams, sunscreens' was the only suspected allergen source category in 10 124 patients (14.6%). A final diagnosis 'allergic contact dermatitis' was stated in 2658 of these patients (26.3%).Compared to a control group, there were significantly more reactions to fragrance mixes I and II, balsam of Peru, methylchloroisothiazolinone/methylisothiazolinone (MCI/MI) and lanolin alcohols. No special pattern of fragrance sensitization could be identified. Among the preservatives, MI was by far the leading allergen, while sensitization to other widely used compounds like parabens or phenoxyethanol was rare. CONCLUSIONS: True allergic reactions to cosmetic ingredients are rarer than generally assumed. Limitation of exposure to MI in leave-on cosmetics and body care products is urgently needed.