Colorful dyes and other vibrant topical creams as treatments for dermatological conditions

This review summarizes the mechanisms, applications, and adverse effects of colorful dyes, such as Castellani’s paint, gentian violet, and potassium permanganate, as well as two other vibrant topical creams—vitamin B₁₂ and indigo naturalis. Certain dyes such as Castellani’s paint, gentian violet, and potassium permanganate were once commonplace topical therapies for cutaneous infections; these dyes are brightly colored on application and have been suggested to be efficacious and well tolerated through case studies as well as controlled studies. Moreover, topical vitamin B₁₂ and topical indigo naturalis creams for atopic dermatitis and psoriasis have been extensively studied through multiple controlled trials and may also be effective, with minimal adverse effects. Understanding the composition and mechanism of action has helped guide the development of these therapies.