The document discusses hyperpigmentation and melasma, outlining the causes and types of hyperpigmentation as well as protocols for treating it using a Yellow Peel chemical peel approach with combinations of retinol, salicylic acid, phytic acid, kojic acid, azelaic acid, and other ingredients over multiple treatments tailored to a patient's skin type and level of hyperpigmentation. The Yellow Peel protocols provide guidance on application times and endpoints based on a patient's phototype and hyperpigmentation severity to safely and effectively treat conditions like melasma, sun damage, and other causes of dark patches and spots on the skin