Vitamin A cream should not be used for a long period of time. Retinoic acid cream is mainly a derivative of vitamin A, with antiproliferative and antikeratinizing effects; it is commonly used in the treatment of psoriasis, acne vulgaris, lichen planus and other skin diseases. When using Vitamin A cream for treatment, it is generally recommended to gradually stop using the drug as prescribed by the doctor to minimize the damage to the skin after the condition has improved significantly. Prolonged use of retinoic acid cream will increase the irritation of the affected skin, resulting in localized flushing, thinning, and in severe cases, secondary infections. If there is serious pain, redness, swelling and ulceration in the affected area during the use of the medication, it is necessary to stop the use of the medication immediately and go to the dermatology department of a regular hospital in time to adjust the appropriate medication for treatment in conjunction with the condition of the patient. In the use of medication, must be under the guidance of a professional physician standardized use, to avoid the cause of the disease to go to medical treatment, unauthorized application of skin damage.