Cystic acne is also known as acne vulgaris. The formation of acne may be related to increased sebum secretion, keratinization of cells around hair follicles, and Propionibacterium acnes infection, etc. It can be eliminated through a combination of general treatment, medication, and phototherapy. 1. General treatment: A light diet, drinking plenty of water, not staying up too late, exercising appropriately, and keeping the face dry and clean can reduce acne symptoms and promote recovery. 2. Medication: (1) Topical medication: topical use of retinoic acid cream, benzoyl peroxide, erythromycin ointment, lincomycin ointment and other drugs can play an anti-inflammatory and antibacterial role. (2) Oral medication: antibiotic drugs such as clarithromycin and doxycycline can inhibit inflammatory reactions and reduce acne symptoms. Female patients with hyperandrogenic manifestations can use birth control pills and spironolactone. 4. Phototherapy: Inhibit the growth of pathogenic bacteria such as Propionibacterium acnes through red and blue light irradiation, so as to achieve the purpose of treatment. If you have cystic acne, it is recommended that you go to the hospital in time, under the guidance of the doctor to carry out regular treatment, do not self-medication.