I've just come off Accutane the dry lips were my constant companion over the last 6 months (still are... but it's only been a week). I found that Blistex Medicated Lip balm was the best for keeping them at least ok. It leaves a bit of a film for a minute but they were less peely.
My biggest thing that I found with them is not to switch up balms all the time, because every time I did, it was like my entire lip peeled off. so I found one that works, and now I won't touch anything else.
Anyways. hope that helps. I went through good and bad periods with dry skin through the entire thing. use lots of moisturizers, drink lots of water. it helps.