Erythrodermic psoriasis is caused by improper treatment of psoriasis, especially the application of hormonal drugs during the acute progression of common psoriasis, or the long-term application of large amounts of corticosteroids, and improper methods of stopping or reducing the dosage. In addition, pustular psoriasis can also appear as joints during the process of pustular regression. This disease accounts for about 1% of psoriasis. Flushing appears at the site of the original psoriasis lesion, which rapidly expands into a large area and eventually presents diffuse flushing infiltration throughout the body. Erythrodermic psoriasis features: 1. Flushing appears at the site of the original psoriasis lesions, rapidly expands into a large area, and finally the whole body shows diffuse flushing infiltration. 2. A large number of scales are shed every day during the onset of the disease, and there is a thick accumulation of scales and crusts on the scalp. At the later stage, there is a large area of skin peeling off from hands and feet. 3.The finger (toe) nails are cloudy, thick, deformed and may fall off. 4.The mouth, pharynx and nasal cavity as well as the conjunctiva of the eyes are congested and red. Often accompanied by fever, chills, headache, general malaise, etc. 5. Superficial lymph nodes are enlarged, and the white blood cell count is increased. Erythrodermic psoriasis is stubborn in nature and is more likely to recur after healing. If it is accompanied by arthritis for a long time, the condition will be more serious. Due to the long delay and repeated attacks, psoriasis patients are gradually weakened and more likely to cause various comorbidities, resulting in adverse consequences. The key to treating psoriasis is to find out the cause and treat it symptomatically. There are very many causative factors for psoriasis, and different therapies and methods are used depending on the cause, and there are many different types of psoriasis, different types, different causative factors, and different properties. The treatment of psoriasis must first be diagnosed, then a treatment plan must be developed, and then the treatment must be carried out.