Acne on the back may be caused by acne or folliculitis, and should be treated with retinoids and antibiotics according to its cause. 1. Acne: Patients with mild lesions can use erythromycin isotretinoin gel, benzoyl peroxide, adapalene and other drugs for local treatment. Doxycycline, minocycline and other systemic medications can be used as appropriate for treatment when inflammation is evident. Severe acne may be treated systemically with isotretinoin as appropriate. If there is an eruption or polymerization of acne can be appropriate application of prednisone and other glucocorticoid drugs for treatment. 2. Folliculitis: topical treatment is the main, bacteria-induced folliculitis can be used externally with erythromycin ointment, mupirocin ointment, etc., Malassezia folliculitis need to be used externally with naftifine ketoconazole and other antifungal drugs. If the skin lesions are generalized or recurrent, systemic drugs can be used for treatment as appropriate. In daily life, attention should be paid to the cleanliness and hygiene of the skin behind, keep the affected area dry, wear loose and comfortable cotton clothing, etc.. At the same time, attention should be paid to the protection of the affected area, avoid scratching, hot water scalding and so on. It is recommended to consult a doctor in time for diagnosis and treatment. The use of specific drugs should be under the guidance of a doctor.