Cystic acne is a severe, grade 4 acne, and is the most severe type of acne in the acne classification. It often occurs on the face, forehead, back, and other areas with severe seborrhea. It mainly manifests as cysts, nodules, and even ruptures, often secondary to infection. After rupture, blood-tinged jelly-like pus flows out, and prognosis is that fistulae and blemishes will form. Cystic acne is often accompanied by the occurrence of blackheads and pimples as well as red papules and pustules. The development of cystic acne is often closely related to genetics, sebaceous gland production, hyperkeratosis of the follicular opening, colonization by Propionibacterium acnes, and infection, especially the genetic aspect. Cystic acne can be an important manifestation of the genetic disorder follicular atresia triad. Daily care measures for cystic acne include the following: 1. Maintain a regular lifestyle, do not stay up late, do not drink alcohol, and have a healthy routine in order to improve the oil secretion of the skin and bring the skin to a healthy state; 2. Promote a diet with less oil, less sugar, and less low-fat milk. Less oil is recommended to patients low-fat diet, do not eat too much fried food. Less sugar is to reduce the intake of sugar, such as reducing the intake of cakes and milk tea. It has been found that low-fat milk aggravates the occurrence and progression of acne. The whey protein in low-fat milk stimulates the liver to secrete insulin-like factors, which are positively correlated with dihydrotestosterone and will accelerate the secretion of sebaceous glands, thus aggravating acne. In addition, foods or fruits containing vitamin A can be taken orally. 3. In terms of daily skin care, cystic acne tends to occur in patients with oily skin. It is recommended to wash the face 2-3 times a day, without over-cleaning or improper cleaning. In the evening, you can use cleansing products containing soap-based cleansing power and wash your face with warm water for 2-3 minutes each time. In the morning, you can use a milder cleanser containing amino acids. After cleansing, use an emollient with an oil-free formula to moisturize the skin. It is recommended that patients with cystic acne not wear makeup.