As far as back acne there is a body wash that proactive makes. The active ingredient is salicylic acid which is basicly asprin. It does something like clean out the hair follicles or somethng. I looked it up once but I don't remember exactly. I think it works ok, I used it for a while. It's not a wonder paste though. I actually just ordered some black soap from a company that has what they advertise as the "real stuff' I will get it soon hopefully. It is supposed to work wonderfully. I'll let you know how it works for me. It cost me incredibly 8 for a 5oz ball of soap and a sample kit because of shipping. The actual soap only cost me 4.50 or something like that which is still fairly pricey but if it works, I can order a pack of 6 and save on shipping next time.

There's a few things you can do, or do them all.

You can buy a loofah or other wash thingy on a stick and try scrubbing your back with that and some salicylic body wash or something.

You could buy this spray thingy, it's a salicylic spray, from nature's cure. You can spray that on your back once you just came out of the shower. Probably get best results after scrubbing with the wash and loofah.

If it's really bad you should take something orally like tetracycline. It will clear up the acne on your face and all over your body.

Are they just spots or eruptions like acne. Do you have any itching sensation? Is there any bleeding or oozing of pus if they break? Do you have similar ones on the chest and the shoulders too?
If it is acne homeopathic medicine has good remedies to get rid of them.
Dr.Venugopal gouri.