Exfoliation Redefined. Dermathod's priming peel pads use a combination of PHA + LHA to gently exfoliate the skin, and promote collagen production. This is a slow releasing exfoliating treatment which should remain on the skin — do not remove! It can be used alone or with any of the Dermathod ampoules. For acne, fine lines, hyperpigmentation. They can also be used on the body for issues like Keratosis Pilaris. For at home use it’s recommended to be used 2-3 times a week LHA's (lipo hydroxy acids) have the same benefits of BHA's, but are much more gentle and hydrating. They work to unclog pores while enhancing living cell production. PHA's (poly hydroxy acids) are hydrating and less irritating than other AHA's, and provide gentle rejuvenation.