it all has to do with genetics too. when im on i have a small amount of ance on back and arms. but during pct or when i take certain things like nolva or cabergoline the acne just gets nuts. all down backs of my arms, my back, back of my neck. luckily not on my face. and these are not your normal pimples but the huge deep unders skin ones that hurt. this is with changing shirts, lava bars, washing sheets, all kinds of acne medicine. its just in my gense. when i was young i had lots of acne. its just how my hormones respond to it. tannin does help hide it