Pimples are usually referred to as acne, and the causes of acne on shoulders may be related to genetics, androgen induction, and propagation of Propionibacterium acnes. Acne on shoulders can be treated with general treatment or medication. 1. Causes (1) Heredity: It may be caused by hereditary factors, resulting in patients being more prone to, and experiencing, the symptoms of acne. (2) Androgen-induced: Acne occurs after puberty due to increased levels of androgens in the body, or when the balance between androgens and estrogens is disrupted resulting in enlarged sebaceous glands and increased sebum production. (3) Proliferation of Propionibacterium acnes: As sebum provides an anaerobic environment for microorganisms such as Propionibacterium acnes to grow in the hair follicles, Propionibacterium acnes hydrolyzes the glycerol esters in sebum to form free fatty acids, which stimulates the proliferation of cells at the follicular ducts and hyperkeratosis, thus blocking sebum excretion and resulting in the formation of acne. 2.Treatment (1) General treatment: use water or suitable cleansing products to remove excess oil, dander and bacterial mixture on the skin surface, and avoid squeezing and scratching the lesions with hands. (2) Medication: Vitamin A acid, benzoyl peroxide, etc. can be used, and oral doxycycline, isotretinoin, etc. can be used for treatment if necessary. It is recommended to consult a doctor in time when acne occurs, and the specific medication needs to be under the guidance of a doctor. It is recommended to go to the hospital when acne occurs, identify the cause, and follow the doctor’s instructions to standardize the treatment.