Retinoic acid cream is topical, for common acne can be applied lightly to the affected area, 1 time / night, before bedtime; ichthyosis and other rashes in the covered area of 1-3 times / day. Vitamin A acid cream is a keratolytic drug, this product is often used as an adjunct to the treatment of psoriasis, acne vulgaris, mucous membrane leukoplakia, flat warts, follicular keratosis, and erythematous furuncle. Vitamin A cream is applied lightly to the affected area once a night, at bedtime, or 1-3 times a day if used for ichthyosis, psoriasis, etc. where the rash is located in a covered area. Topical use of this product may cause such as burning sensation, flaking, erythema. There are certain contraindications to the use of the drug, it should be contraindicated in the eye, women during breastfeeding, women during the first 3 months of pregnancy. In addition, it should not be used in patients with rosacea, sunburn, eczema, acute and subacute dermatitis; sunlight should be avoided during treatment. Vitamin A acid cream should be used under the guidance of a physician, if serious adverse reactions occur, stop using it in time to wash it off and consult a doctor in time.