It can be due to folliculitis or acne on back
and shoulder acne are quite difficult to treat compared to acne on
other parts of the body. Thoroughly wash your body everyday, especially the back and shoulder part using a back brush and frequently change your bed sheet, as it is conducive for bacterial growth. Engage in a diet that is low in sugar and fat but is rich in vitamins. This prevents acne by preventing the buildup of excess oil on the skin.