Randomized, double-blind, parallel-controlled clinical study on the treatment of Sjögren's syndrome with nourishing yin and moisturizing dryness method

INTERVENTION: treatment group:Qingzao Capsules, take 600mg each time, 3 times a day, dissolved in warm water;Control group:Placebo of Qingzao Capsules, taken 3 times a day, 600mg each time, dissolved in warm water; CONDITION: Sjögren's syndrome PRIMARY OUTCOME: the EULAR Sjögren's syndrome patient reported index; SECONDARY OUTCOME: EULAR Sjögren's Syndrome Disease Activity Index;VAS score for dry eyes/dry mouth;Traditional Chinese Medicine syndrome score;Overall effective rate;Physician's Global Assessment;Patient's Global Assessment ;Functional Assessment of Chronic Illness Therapy‐Fatigue;Schirmer test;static salivary flow rate;Laboratory indicators; INCLUSION CRITERIA: (1) Meet the diagnostic criteria of pSS in Western medicine; (2) Meet the diagnostic criteria for Yin deficiency and heat‐toxicity syndrome in traditional Chinese medicine; (3) Age is greater than or equal to 18 and less than or equal to 70 years old; (4) ESSPRI (dryness/fatigue) is greater than or equal to 4; (5) During screening, if patients are currently using disease‐modifying antirheumatic drugs, the treatment dose should be stable for at least 12 weeks. (6) During screening, if the patient is currently using glucocorticoids (prednisone or other equivalent hormones) for at least 12 weeks at a stable dose of less than or equal to 10mg/d, and this dose is not to be increased in subsequent treatment. (7) The subjects agree to participate in this study and sign the informed consent form.