First, the current onset of psoriasis Its onset often appears obvious seasonal change pattern, from the distribution of time: the most onset of spring, aggravation season to winter and spring, while the remission season to psoriasis-related knowledge of the summer most. Population distribution: female onset is earlier than male and more than male, and the number of patients aged 20 to 45 accounts for 78% of the total number of patients. As of 2007, the number of psoriasis patients in China has reached 4.58 million. The incidence of psoriasis is higher in cities than in rural areas, which is mostly thought to be related to the serious environmental pollution in cities and the high psychological pressure of people. Because the disease is stubborn and difficult to treat, it is still listed as an important research topic in the field of dermatology in the world today and is one of the key prevention and treatment diseases in dermatology worldwide. The so-called ringworm medically refers to a number of skin diseases caused by fungal infections, such as ringworm of the head, ringworm of the femur, ringworm of the body, ringworm of the hands and feet, ringworm of the fingernails, and so on. Fungal hyphae or fungal spores can often be found when the localized dander of these ringworm is placed under a microscope, whereas psoriasis is not caused by a fungal infection. It has a complex pathogenesis, and treatment with antifungal drugs is often ineffective. Therefore, do not look to the text to make sense of it. Clinically, we find that many patients take antifungal medications or use ringworm topicals indiscriminately, that are not symptomatic and can sometimes aggravate or delay the condition. Because psoriasis lesions are covered with silvery-white scales and will have bleeding spots after the white scales peel off. Very characteristic, the medical term for it is psoriasis. III. Factors causing or triggering psoriasis Psoriasis is not contagious, but its cause is complex and the cause is not yet clear. In recent years, most scholars believe that it is related to genetics (according to clinical observations, the disease often has a family history and a hereditary tendency. Foreigners have reported a family history of 30% – 50%, and even some individuals emphasize up to 100%. Domestic reports have a family history of about 10% to 20%), infection, metabolic disorders, immune dysfunction, endocrine disorders, environmental and other related. The main triggering causes of psoriasis are the following most common in outpatient clinics: Prevention of infection Local infection is an important cause of psoriasis, especially after a cold, complicated by tonsillitis and bronchitis, which requires active treatment to minimize the course of the disease. Those who have recurrent inflammation of the tonsils, which is closely related to psoriasis attacks, can consider tonsillectomy, which is especially important for adolescent patients. Mental factors Daily life due to work pressure, poor rest, excessive mental tension resulting in emotional instability, worry and depression, and can not reasonably adjust the maintenance of the skin or long-term diet is not regular overeating, excessive alcohol consumption. Excessive tea drinking and external causes such as cold, fever, tonsillitis, low immune function and lack of resistance lead to the onset and recurrence of psoriasis, and mental factors such as excessive mental tension, anxious temperament and emotional depression are the main causes, accounting for about 18.6% of the total incidence of psoriasis in China. Excessive mental tension can produce a series of psychological or physiological reactions, prompting neuroendocrine disorders, damaging the body’s immune defense system and metabolic disorders of certain enzymes, thus promoting the occurrence of psoriasis, so in case of irresistible or unpredictable unexpected things patients should try to control their emotions, maintain a calm mood and ensure sufficient sleep time. Allergic factors Skin allergy is one of the main reasons for triggering psoriasis. Allergies due to diet or medication, or contact with certain substances can often trigger the occurrence of psoriasis. After each relapse, patients need to carefully recall what they have taken or touched a certain substance in the recent past, which makes the skin itchy, followed by erythema symptoms, and they should try to avoid contact in the future, such as certain seafood, beef and mutton, spicy food and other substances. If necessary, allergen testing should be performed. Exogenous stimulation Such as trauma, frostbite, needle prick injury, high temperature bathing and back rubbing can aggravate and induce the occurrence of psoriasis. Fourth, the clinical can be divided into several types and what are their manifestations. According to the clinical characteristics of psoriasis, it can be divided into common type, arthritic type, pustular type and erythrodermic type, of which common type accounts for more than 99%. Other types are mostly induced by the external use of irritating drugs, systematic use of glucocorticoids, sudden discontinuation of drugs in the process of immunosuppression and infection, mental stress, etc. in common psoriasis. The rash generally occurs on the scalp, trunk and extremities, and is a red papule on the skin, which gradually expands and fuses into patches or plaques, with thick silvery-white phosphorous flakes on the surface, irregular in shape, some have a map or island-like appearance, some lesions are smaller, more, and have a starry appearance, with layers of scales falling off, and a thin layer of red membrane can be seen by gently scraping off the flakes, and the red membrane can be seen by scraping off the red membrane. Small bleeding spots, also known as sieve bleeding in medicine.