I've done about 4 treatments just fine.The 5th treatment I actually had some frosting occur pretty aggressively? I do these at home as I cannot afford a dermatologist or an esthetician. The brown spots are on the corners of my mouth and a little bit under my lip/chin area. At first during the first week of healing the brown spots were very prominent. After day 3/4 it peeled and it was about 70% lighter after. But Since I have light skin, these light brown spots are pretty noticeable.