I. Prevalence Compared with the prevalence rate of l-2% in Europe and America, the prevalence rate of psoriasis in China is relatively low, which is 0.123% (1982). Because of the large population in China, the absolute number of psoriasis patients is high and is increasing year by year. Second, classification of severity Before formulating a reasonable treatment plan for psoriasis patients, clinicians need to assess the severity of psoriasis. A simple way to define the severity of psoriasis is called the tenth rule: namely, body surface area affected (BSA) >10% (the area of 10 palms) or psoriasis area and severity index (PASI) >lO or skin disease quality of life index (DLQI) >10 is considered severe psoriasis; BSA <3% is mild, and 3% to 10% is moderate. Many factors such as the extent of skin lesions, location and impact on quality of life should also be considered. The purpose of psoriasis treatment is to control the disease, slow down the process of development to the whole body, reduce symptoms such as erythema, scaling and local patch thickening, stabilize the disease, avoid recurrence, avoid side effects as far as possible and improve the quality of life of patients. Communication with patients and evaluation of their conditions during treatment is an important part of treatment. When the effect of single therapy is not obvious in patients with moderate or severe psoriasis, combined, rotational or sequential therapy should be given. The following treatment principles should be followed: ①Regular: emphasize the use of currently accepted therapeutic drugs and methods in the dermatological sciences. ②Safety: All treatment methods should be used to ensure the safety of the patient as the first priority, and serious adverse reactions should not occur in pursuit of recent efficacy. Patients should not be made to apply methods that are harmful to their health for a long time without the guidance of a physician. ③Individualization: When choosing a treatment plan, the condition, needs, tolerance, affordability, previous treatment history and adverse reactions of drugs of patients with psoriasis should be comprehensively considered, and the treatment plan should be selected and formulated in a comprehensive and reasonable manner. Treatment plan for each type of psoriasis: ①Mild psoriasis: external drug treatment is the main treatment, phototherapy can be considered, and internal drug treatment if necessary, but possible adverse drug reactions must be considered. ②Moderate to severe psoriasis: ultraviolet light, photochemotherapy, methotrexate, cyclosporine, retinoids, biological agents, combined therapy. ③Pustular psoriasis: retinoids, methotrexate, cyclosporine, phototherapy/photochemotherapy, biologics, supportive therapy, combination therapy. ④Erythrodermic psoriasis: retinoic acid, cyclosporine, methotrexate, biologic agents, supportive therapy, combination therapy. ⑤ Arthritic psoriasis: non-steroidal anti-inflammatory drugs, methotrexate, leflunomide, cyclosporine, azathioprine, lujiazosulfapyridine, biological agents, supportive therapy, combined therapy. Topical treatment of psoriasis It is advisable to use mild protective and emollient agents in the acute phase of psoriasis; stronger drugs can be used in the stable and receding phases, but they should start at low concentrations. Generally, two times a day. (1) Emollient: Vaseline, glycerin, mineral oil, urea, etc. ② keratin promoter: 2% to 5% coal tar or bran distillate, 5% to 10% black bean distillate, 3% salicylic acid, 3% to 5% sulfur, 0.1% to 0.5% dithranol, 0.001% carbostriol ointment, 5% fish lithin. ③Keratolytic agent: 5%-10% salicylic acid, 10% rezosin, 10% sulfur, 20% urea, 5%-lo% Vulinic acid, o.1% vincristine, 10%-30% ichthyolipid. Glucocorticoids: low potency: 0.5%-2.5% hydrocortisone acid, 0.25%-l% methylprednisolone; medium potency: 0.1% hydrocortisone butyrate, 0.1% dexamethasone, 0.1% tretinoin 0.03% flumethasone pivalate, 0.1% moson furoate; strong potency: 0.5% botrytisine, 0.1% betamethasone valerate, 0.1% harcionide; extra strong potency: 0.05% clobetasone propionate. 0.05% clobetasol propionate, 0.05% halometasone, 0.05% difluazone. ⑤ Retinoic acid: 0.025% 0.1% all-trans retinoic acid, 0.05% isotretinoin, 0.1% adapalene gel, 0.01%, 0.05% and 0.1% tazarotene, etc. (6) Vitamin D3 derivatives: carboxytriol, tacalcitol, osteoporotic triol. (7) Dithranol: 0.1% to 0.5% dithranol ointment, cream, paste and compound preparation. (8) Tar: 5% coal tar, l%-5% coal tar, 5%-10% black bean distillate, 5% bran distillate. ⑨ cytotoxic drugs: 0.05% aqueous solution of nitrogen mustard hydrochloride or ethanol solution. ⑩Other: 0.01% a 0.025% chorine ointment, 10% a 15% camptothecin, etc. Tazarotene, medium- and strong-acting glucocorticosteroids, and carboplatinol can be used as the first-line drugs for local treatment. V. Physical therapy Long-wave ultraviolet (UVA): wavelength of 320-400 nm, the application of UVA irradiation alone will produce mild to moderate improvement, not recommended at the same time for other forms of phototherapy, UVA therapy is most commonly used as a component of PUVA therapy Photochemotherapy (PUVA): photochemotherapy is a combination of oral or topical psoralen (8- MOP, 5 a MOP) with UVA, a few can also apply UVB (290-320rim) method. It is mainly used for the treatment of moderate to severe psoriasis. These include generalized psoriasis vulgaris, limited plaque psoriasis (with topical psoralen + UVA), erythrodermic psoriasis and pustular psoriasis. Oral psoralen can cause gastrointestinal symptoms, such as nausea; high UVA exposure can cause skin erythema, burning, blistering, etc. Long-term application of PUVA can cause skin aging, pigmentation and skin cancer; there is an increased risk of cataract. Broad-spectrum UVB: Medium-wave UVB with a wavelength of 290-320 nm. It is commonly used for the treatment of moderate and severe psoriasis, or local stubborn plaques. However, it can cause erythema, sunburn and hyperpigmentation. Long-term exposure has the potential to cause cancer. Broad-spectrum UVB can be used in combination with internal and/or external medications to increase the efficacy. Narrow-spectrum UVB: Medium-wave UVB with a wavelength of 311 rim (308, 310, 311, 312 am). It has good efficacy in treating psoriasis with little side effects such as erythema, hyperpigmentation, DNA damage and carcinogenesis. Narrow-spectrum UVB treatment is superior to broad-spectrum UVB and safer than PUVA treatment. The effectiveness of narrow-spectrum UVB is the same as the early stages of PUVA, but the remission period is not durable. Narrow-spectrum UVB can be used alone or in combination with some topical preparations and internal drugs. It is one of the more widely used phototherapy for all types of psoriasis vulgaris. Patients with erythrodermic and pustular psoriasis should be used with caution. Anti-infective drugs: Bacterial, viral or fungal infection is an important cause of psoriasis, and infection can be controlled by applying drugs. The purpose of treating psoriasis can be achieved. It is mainly applied to punctate psoriasis, common psoriasis and some erythrodermic and pustular psoriasis accompanied by upper respiratory tract infection, and the corresponding antibiotics or antibacterial drugs effective against Streptococcus haemolyticus can be used, such as penicillin, erythromycin and cephalosporin. Methotrexate: It is an effective psoriasis treatment drug. Methotrexate is applied according to the severity of the disease, tolerance, urgency of treatment and the patient's compliance with medical advice. It is mainly used for erythrodermic psoriasis, arthritic psoriasis, acute generalized pustular psoriasis, psoriasis with severe functional effects, such as palmar and plantar, and extensive plaque psoriasis. Retinoic acid: Avia is effective in the treatment of plaque, pustular, palmoplantar, drip, and erythrodermic psoriasis. 57% reduction in psoriatic rash and severity was observed at 12 weeks. Significant improvement was observed in 70% of severe patients after 1 year of treatment. It is safe for long-term use. There is no time frame, so continued treatment is effective. Although symptoms of bone changes are rare, long-term use should be limited in some patients who develop calcification of ligaments and tendons. Preferred treatment: pustular psoriasis, erythrodermic psoriasis; in combination with other treatments: palmoplantar pustulosis, plaque psoriasis; alone therapy or adjuvant therapy: arthritic psoriasis. Cyclosporine: has definite efficacy in psoriasis. It is relatively safe when applied at doses <5 mg?kg--?d" in strict compliance with dermatology. Nephrotoxicity is its main adverse effect. Therefore it should be carefully monitored and a nephrologist should be consulted if necessary. Severe psoriasis may recur up to 2 months after cessation of cyclosporine treatment. It is effective in all types of psoriasis but should be used in patients with severe and failed psoriasis treated with various therapies. Glucocorticoids: Application of glucocorticoids may lead to erythrodermic or generalized pustular psoriasis. Therefore they should only be applied when deemed absolutely necessary by the dermatologist. Indications: Erythrodermic psoriasis that is difficult to control; generalized pustular psoriasis in which other drugs are ineffective or contraindicated; acute polyarthritic psoriasis that can cause severe joint damage. Other drugs that may be applied: salazosulfapyridine, tacrolimus, aminophenazone, methylsulfonamides, levamisole, transfer factor, colchicine, vitamins. Biological agents (etanercept): etanercept is a human-derived TNF a receptor-only antibody fusion protein, commonly known as recombinant human type II TNF-ot receptor antibody fusion protein for injection. It was approved by the FDA in 1998 for the treatment of rheumatoid arthritis, in 2002 for the treatment of psoriatic arthritis and in 2004 for the treatment of psoriasis vulgaris. Etanercept is the only biological agent approved by the FDA for the treatment of psoriasis in China, and there are other agents currently in clinical trials. The drug must be selected for treatment of moderate or severe psoriasis with a PASI score ≥ 10 and significantly affects the patient's quality of life (DLQI > 10); the condition persists for 6 months. Treatment is ineffective and systemic therapy is required. In addition, at least one of the following must be met: (i) the condition is at a high risk level and the use of standard therapy is difficult due to drug-related toxicity; (ii) the standard systemic therapy is not tolerated; (iii) the standard therapy is not effective; (iv) repeated hospitalizations are necessary to control the condition; (v) the use of systemic therapy medications is hampered by comorbidities; (vi) severe erythrodermic and pustular psoriasis; (vii) arthritic psoriasis. Using the method of evidence-based medicine, the clinical manifestations of psoriasis are combined with the dialectical diagnosis of Chinese medicine to summarize the main Chinese medicine syndromes, treatment principles and Chinese medicines. (1) Blood-heat and wind-rich type (common progressive stage): the treatment is to clear heat and cool the blood to remove wind, and the formula is based on cooling the blood and removing wind. ②Blood stasis in the skin type (unusual stationary phase): the treatment is to invigorate the Blood and remove blood stasis. (③) Blood deficiency and wind dryness (unusual waning phase): the treatment is to nourish Blood and remove wind. (4) Damp-heat type (limited or palmoplantar pustular): the treatment is to clear heat and relieve dampness, using Cao Xie Xue Damp Tang plus or minus. (⑤) Fire-poisoning type (generalized pustularity): the treatment is to remove the fire and detoxify the toxin, using Huang Lian Detoxification Tang with Wu Wei Disinfection Drink. (6) Wind-dampness blocking the ligaments (arthropathic): the treatment is to remove wind and dampness, invigorate blood and open the ligaments, using Douwuxiaosheng Tang and Santo Plus and Minus. (7) Heat poisoning and Yin injury (erythrodermic psoriasis): the treatment is to clear heat and detoxify, nourish Yin and cool the Blood. The formula is based on Qing Ying Tang and Sheng Wei Wan Wan. Lei Gong Tang and Kunming Shan Hai Tang have reliable efficacy in common, palmoplantar pustular and arthritic psoriasis. Compound Qing Dai Capsules (Pills), Yu Jin Yin Qi Tablets, Yin Qi Ling and Yin Qi Punch are mainly for clearing heat and detoxifying toxins, and are suitable for the treatment of common psoriasis and other types of adjuvant therapy. Danshen and viper antithrombin injection are mainly herbal medicines for activating blood circulation and removing blood stasis; Qingkailin, licorice sweetener and Chuansuuning injection are mainly herbal medicines for clearing heat and detoxifying, and Huangqi injection is mainly used for regulating immunity. Psychotherapy Psychotherapy is to use the principles and methods of medical psychology, through the words, expressions, posture, attitude and behavior of medical personnel, or through the corresponding instruments and environment to change the patient’s feelings, awareness, emotions, personality, attitude and behavior, so that the patient can enhance confidence, eliminate tension, to promote the patient’s compensation, the recovery of regulatory functions, so as to achieve the purpose of treating the disease. Psychotherapy can be individual therapy, group therapy, family therapy and social therapy, and biofeedback therapy and abdominal breathing training can also be used to enhance the patient’s intrinsic immune regulation function. Prevention The prevention of psoriasis currently refers to avoiding the aggravation and relapse of the patient’s disease, i.e. prolonging the remission period. It is especially important for psoriasis patients to maintain good living habits and not to be addicted to smoking and alcohol. In addition, colds and inflammation of the throat can cause recurrence or aggravation of the disease. Proper physical exercise, improving physical fitness and maintaining mental and physical health are the keys to preventing psoriasis. As for the patient’s diet taboos need to vary from person to person, the patient can decide the trade-off depending on his or her skin reaction. Mental and psychological factors play an important part in the development of psoriasis, so relaxation is also important in prevention.