Face powders along with sweat or oily creams can form a paste and block the natural skin pores, thereby aggravating acne. Some perfumes in powders and creams can also cause troublesome rashes and irreversible pigmentation.
In general it is best to avoid make up if possible. However women find it extremely embarassing to go out when their acne is active and therefore if you need to use make u, it is best to stick to something that is non-greasy (the brand does not really matter) and wash it off straight away after you get home. Facial powders are a complete no-no.