how bad is it, when did it start in the cycle, what is the weather like where you live, what is your personal hygiene like, what sort of clothes do you wear (cotton, polyester etc etc)
many cases of mild acne can be avoided with good hygiene, suitable clothing, and a few topical cleansers/disinfectants. tanning will help also, but take it easy with the creams
roaccutane should be reserved for stubborn cases imo, its nasty stuff. lots of sides. try to get on top of the problem early in the cycle, prevention is better than cure