Dry, itchy, red skin on the face is a sign of thinning skin stratum corneum and impaired barrier function. After the barrier function is damaged, the skin’s ability to lock water decreases, which leads to dry flaking, increased susceptibility, and easy redness and itching. Common causes include: 1. excessive washing, such as using sulfur soap and oil-control cleanser, which damages the epidermal stratum corneum and sebaceous glands. 2. the influence of certain oral and topical drugs, such as retinoids, which can inhibit the secretion of sebaceous glands and the proliferation and differentiation of epidermal cells, thus reducing the secretion of sebaceous glands and thinning the epidermis. 3. the factors of cosmetics, such as chemical peeling agents and glucocorticoids containing 4.The adverse stimulation of external environment is also a triggering factor. After the appearance of red spots and dry itch, we should try to avoid the above factors, use moisturizing skin care products to repair the skin barrier, and combine oral and topical anti-allergy medication for heavier symptoms.