Symptoms of psoriasis: erythema, white scales, thin film, punctate hemorrhage, itchy skin, etc. Symptoms of psoriasis: at the beginning of inflammatory red papules, about the size of a grain of corn to mung bean, and later gradually expand or merge to become brownish-red plaques, with clear boundaries, surrounded by inflammatory red halo, with obvious infiltration of the base, and the surface covered with multiple layers of dry grayish-white or silvery-white scales. Gently scrape off the surface scales, gradually reveal a layer of light red shiny translucent film, called film phenomenon. When the film is scraped again, small bleeding spots appear, which is called punctate hemorrhagic phenomenon. White scales, shiny film and punctate hemorrhage are important features in the diagnosis of psoriasis, which is called the triad sign. Lesion morphology: dribbling, coin-shaped, map-like, ring-like, band-like, generalized, seborrheic dermatitis-like, eczema-like, oyster-shell-like, lichen planus-like, chronic hypertrophy, wart-like and so on. The key to treating psoriasis: find out the cause of the disease, symptomatic treatment. Psoriasis is caused by a very large number of factors, according to the different causes of the implementation of different therapeutic methods, psoriasis disease type is also very much, different types, different causative factors, different nature of the use of different therapeutic methods. Treatment of psoriasis should first be diagnosed, and then formulate a treatment plan, and then carry out the treatment.