Xanthotoxin Products | Cleanchem - Xanthotoxin is a naturally occurring compound found in certain plants, including the root of the plant *Ammi majus*, used in traditional medicine. It is a photosensitizing agent and has been studied for its potential use in phototherapy to treat skin conditions like vitiligo. Xanthotoxin induces pigmentation in the skin when exposed to ultraviolet light, which is beneficial for treating conditions where skin pigmentation is lost. However, it can cause skin irritation and should be used with caution.