Some acne on the shoulders, neck and back result from really tight clothes, or sometimes if you don't change clothes after working out, that causes it too.
Try an acne body wash, neutrogena has some: http://www.drugstore.com/products/prod.asp?pid=211775&catid=45531

That should get rid of the current acne and help prevent it in the future! :]it is recommended that a Salicylic Acid soap be used. It contains beta hydroxy, which is used not only for the inflammationof acne, but is also effective at removing dead skin cells. Products like Clearisil and Pro Active have benzoyl peroxide in them. Benzoyl peroxide works by increasing the amount of oxygen in the pores. Acne cannot survive when there is an abundance of oxygen in the pores they are attempting to attack. If the form of body acne is severe, a prescription will be needed for treatment by a dermatologist. Some of the more common prescriptions are for antibiotics, Retin-A and Accutane.

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