Can't tell you why you're getting it. But hey, lets solve the problem!
When I got acne on my second cycle, I used this product and it helped a good deal. However, you mentioned you had acne on your back? Man, I think you should just lay off they pct/roids if it's really that bad. Unless you can somehow get these pads on you're back !
http://www.walgreens.com/store/catal...sku=sku1939724
Best of luck!
PO