It is possible to burn out your oil glands with it and not get acne again for several years. You'll need 80mg+/day for 6 months or more to do it though. I like orals, winny, ox etc so I wouldn't take that much. I just use 20mg/day all the time and my liver values are fine and I have no acne. At that dose I can even tan in the sun without burning. So it's perfect for me.