I've been on Differin since June 16th, and have been using it every night since July 13th (the first two weeks I used every third night, the second two weeks I used every other night). My skin lately has been looking pretty bad - it just seems to get worse and worse.
I know Differin takes a while to start really working, and that purging is often a painful part of the process, but I'm starting to get antsy, since it's been a good six weeks of using every night and no end in sight of it. My skin looked great when I first started using it and wasn't using it every night, but these past four weeks (and past week especially) have been more breakouts and clogged pores than usual.
It has helped with the blackheads on my nose (and almost immediately when I started using it I noticed a difference) and has help with how oily my skin gets, so there have been some positives. But my overall skin quality looks poorer at the moment (it also seems like my skin is less resistant to it now, rather than more).
Am I just being impatient and need to stick with it for a few more weeks? I'm thinking of scaling back to every other night and see if that helps.