I have rash and pimples on back.

Hi Thanks for your query.Body acne commonly occurs on the neck, chest, back and arms— it is slightly different that facial acne and may be more difficult to treat.  Here are some treatment recommendations to help clear up your skin. Bathe right after you exercise. Working up a sweat might be behind your chronic acne breakouts. Sweat during exercise is a major trigger of body acne, "when you sweat a lot, you usually develop some pimples." To remove all the oil on your body use a medicated wash containing salicylic acid or benzoyl peroxide. Wear loose fitting clothes preferably cotton. Short term oral antibiotics to get inflammation under control,  retinoid creams are helpful. Severe boils may require oral Isotretinoin shrinks oil glands, helps prevent clogs, reduces inflammation, and reduces acne bacteria.