1, common psoriasis Common psoriasis is the most common type of clinical psoriasis, the incidence of psoriasis accounts for more than 95%, the lesions start as red pinheads or chestnut-sized papules, and then gradually expand or fuse into patches, bright red or deep red, higher than the skin, basal infiltration is obvious, the surface is covered with multiple layers of gray or silvery white scales, gently scrape off the surface scales, revealing a layer of light red shiny translucent Film, if the film is scraped away again, there will be dotted bleeding spots, called dotted bleeding phenomenon. The lesions can occur in all parts of the body, with scalp, extremities and trunk being the most common. 2, erythrodermic psoriasis This type of psoriasis is mostly transformed from common psoriasis due to improper treatment or other reasons. Patients show diffuse flushing all over the body and a large amount of flaking. It is often accompanied by fever, joint pain and other systemic symptoms. The course of the disease is chronic, stubborn and difficult to treat. 3.Arthritic psoriasis Arthritic psoriasis is accompanied by joint damage in addition to rash, and joint symptoms are often reduced or aggravated at the same time as skin damage, manifesting as joint swelling and pain, restricted movement, and deformity can also occur. 4, pustular psoriasis This type of psoriasis is less common, but stubborn and difficult to treat. Clinically, it is divided into two types, namely, generalized pustular psoriasis and palmoplantar pustular psoriasis. In the former, the patient has diffuse erythema all over the body, and a large number of small, dense, needle-head to chestnut-sized sterile pustules appear on the spots, with recurrent attacks. The palmoplantar type lesions are limited to the hands and feet and occur mostly on the palms of both hands and the plantar areas.