For advanced grades of acne, Tretinoin is one of the most powerful exfoliating tools that we have. It increases skin cell turnover which results in increased shedding of dead skin and excellent exfoliation. This is the reason why medications such as Retin-A, Differin, and Tazorac are commonly prescribed to people with acne. The downside of tretinoin is that it often leaves the skin red and flaky for a period of time while you are adjusting to it. This period of adjustment can last from a couple of weeks to a couple of months. For those that want something less irritating, we have medical-strength retinol which is very effective as well.