If the patient has acne on the stomach, the possible causes are as follows: 1. It may be caused by a certain inflammation in the area, and the inflammation may be folliculitis. Folliculitis in this area may be caused by a specific bacterial infection in the patient or by soft tissue damage in the area, which eventually leads to secondary infection; 2. It may also be a phenomenon of active local sebaceous gland secretion. Active sebaceous glands secrete sebum, which, if not discharged from the skin surface in a timely manner, may collect in the sebaceous ducts and eventually form certain acne. In the case of acne caused by infectious factors, anti-infection treatment, such as local topical application of fusidic acid cream for anti-inflammatory treatment, is needed in a timely manner.