Oral dryness is an autoimmune disease characterized by the progressive destruction of exocrine glands, resulting in dryness of mucous membrane and conjunctiva, and accompanied by various autoimmune symptoms. If the lesion is limited to the exocrine gland itself, it is called primary desiccation syndrome: if it is accompanied by other autoimmune diseases, such as rheumatoid arthritis, it is called secondary desiccation syndrome. 1.Ocular manifestations: dry conjunctivitis, keratitis. 2.Oral manifestations: dry mouth, difficulty in speech, chewing and swallowing, poor retention of dentures. 3.Salivary gland enlargement: parotid gland is the most common, mostly bilateral. 4.Other Exocrine gland involvement manifestations: upper and lower respiratory secretion glands, skin exocrine glands, dry and crusty nasal mucosa, dry larynx and bronchi, hoarseness, chronic dry cough. 5. Connective tissue diseases: rheumatoid arthritis, systemic lupus erythematosus, scleroderma. 6. Exocrine gland organ lesion manifestations: reduced renal concentration capacity, renal tubular acidosis, but rarely renal failure, nasopharyngeal duct obstruction caused by otitis media, sensory nerve peripheral neuritis, polymyositis. Treatment: Symptomatic treatment: Dry eyes can be treated with 0.5% methylcellulose drops to relieve the symptoms of dry eyes. Dry mouth can be moistened with artificial saliva to relieve the discomfort. Also use Mao Guo Yun Xiang Xiang Alkali to stimulate saliva secretion.