“Third time is the charm?”

First course was 2X20mg per day for about 10 months. Second course was 2X20mg per day for a week every month. It has worked for the cystic acne, but I still have problems with clogged pores, mostly on my forehead.

I do not really get many large pimples, but more clogged pores with whiteheads, blackhead and the occasional small pimple. Can going on a third course have any effect on my problem or can it actually make it worse? I have tried a lot of different topical solutions and using Differen now, but does not really help much.