Try washing the area with a wash of 2.5% salicylic acid. You should also wear loose fitting, breathable clothes and make sure to wash area thoroughly if you use conditioner.
To rid your skin of acne, you should cleanse it thoroughly daily with a facial cleanser. Some people also believe toothpaste on pimples overnight helps dry them out.
remedies for back acne is cleaning the area, Sleep on your stomach, keep back from rubbing. try masks such as tomato, oatmeal, or mint. drink plenty of water and exercise.
You would treat this acne like you would treat acne that exists anywhere else. Because of the location someone else will have to apply acne medication. If it's really bad you might want to see a dermatologist.