(1) Wash your face with water to remove the mixture of oil, dander and bacteria from the skin surface, but do not over-wash. (2) Do not squeeze or scratch the acne with your hands. (3) In addition, do not use oil and grease, powder skin care cosmetics and ointments and creams containing glucocorticoids. 2, topical drug treatment (1) retinoic acid drugs ① 0.025% ~ 0.1% retinoic acid (all-trans retinoic acid) cream or gel: this drug can regulate the differentiation of epidermal keratin-forming cells. This drug can regulate the differentiation of epidermal keratin-forming cells and make acne dissolve and discharge. The skin is mildly irritated at the beginning of 5-12 d, such as local flushing, flaking, tightness or burning sensation, but it can gradually disappear. Therefore, it should be used from a low concentration and applied once a night. Avoid increasing drug irritation after light exposure, and apply topically once a week after symptoms improve. ②13th cis-retinoic acid gel: regulate the differentiation of epidermal keratin-forming cells and reduce sebum secretion, once or twice a day. (③2nd generation retinoids: 0.1% adapalene gel, once a night, has good efficacy in treating mild and moderate acne. 0.1% tazarotene cream or gel, used once every other night to reduce local irritation. (2) Benzoyl peroxide This drug is a peroxide that slowly releases neo-oxygen and benzoic acid after topical application, which has the effects of killing Propionibacterium acnes, dissolving acne and astringency. It can be formulated into 2.5%, 5% and 10% lotions, emulsions or gels of different concentrations, and should be used from a low concentration. A gel containing 5% peroxymethylphenidate and 3% erythromycin can improve the efficacy. (3) Antibiotics Erythromycin, chloramphenicol or clindamycin (clindamycin) formulated with ethanol or propylene glycol at a concentration of 1% to 2% are more effective. 1% clindamycin phosphate solution is a water-soluble emulsion free of oil and ethanol for acne patients with dry and sensitive skin. l% clindamycin solution is also effective. (4) Azelaic acid This drug can reduce the flora on the skin surface, hair follicles and sebaceous glands, and especially has an inhibitory effect on Propionibacterium acnes and acne lysis, and is effective for different types of acne. It can be used externally as a 15%-20% cream, with local erythema and stinging as adverse effects. (5) Selenium disulfide 2.5% Selenium disulfide lotion has the effect of inhibiting fungi, parasites and bacteria, and can reduce the free fatty acid content of the skin. After cleansing the skin, apply the lotion evenly with slight dilution on the part of seborrhea, and then wash with water after about 20 minutes. (6) Sulfur lotion 5-10% sulfur lotion has the effect of regulating the differentiation of keratin-forming cells and reducing the free fatty acid content of the skin, and also has a certain inhibitory effect on Propionibacterium acnes.