Avitamin A usually refers to Avitamin A capsules, the initial dose of 25 or 30mg for adults, after 2 to 4 weeks of satisfactory results; maintenance dose of 25 to 50mg per day, usually 6 to 8 weeks to achieve the desired effect. Avicenna capsule is clinically used for severe psoriasis and severe keratosis pilaris, such as erythrodermic psoriasis, congenital ichthyosis, hairy erythematous furuncle and so on. Proper use of the drug is required under the guidance of a medical professional. This product can cause dry lips, dry mucous membranes and epithelium, lipitis, dry mouth, dry mouth, stomatitis, gingivitis, alopecia, generalized thinning of the skin and other adverse reactions after the use of the drug. Usually recovered after stopping the drug. This product is contraindicated in people who are allergic to this product and the ingredients contained in it, people who are allergic to other retinoids, patients with severe hepatic or renal impairment, patients with chronic hyperlipidemia, pregnant and lactating women. Combination with tetracycline, methotrexate, vitamin A and other drugs is prohibited. Patients should use the drug under the guidance of a professional physician and strictly follow the doctor’s instructions.