Tretinoin
"I've been using this for about 3 weeks now and at first there was a lot of peeling. And one day I think I used too much and my cheecks became inflamed and irritated. It looked like I had a really bad sun burn in the fall. As of right now this gel has only made my skin worst. I have dark marks on my cheeks and in the corner of my mouth. I look horrible! These reviews say to keep going and be patient. But if I don't see results soon I will be forced to stop."