2025 Volume 135 Issue 3 Pages 625-636
Cocamidopropyl betaine (CAPB) is an amphoteric surfactant derived from coconut oil fatty acids; it is commonly used in shampoos. To identify the causes of persistent scalp and facial dermatitis, we conducted patch tests using the shampoos that the patients had used, along with CAPB-related compounds. The results confirmed that CAPB-related compounds in the shampoos were one of the causative factors for their dermatitis. In this report, we present seven cases (2 males and 5 females, aged 12 to 69 years, with disease durations ranging from 1.5 months to several years) in which scalp and facial dermatitis improved after switching to CAPB-free shampoos. Patch testing for CAPB has proven valuable in diagnosing shampoo-induced allergic contact dermatitis.
