1. Incidence of the disease: In recent years, the incidence of the disease has been increasing year by year, especially in children, along with the declining air quality and pollution of the living room and diet, accounting for the highest incidence of chronic cough. 2. Clinical features: 1) cough for more than 4 weeks, mainly irritating cough, aggravated at night and in the early morning; 2) ineffective antibiotic treatment, obvious relief after nebulized inhalation; 3) personal history of eczema or skin allergy; 4) some patients have a family history of allergy; 5) no fever, no wheezing, no obvious abnormalities on chest X-ray; 6) some patients have elevated eosinophils. 3. Treatment: 1) Oxygen-driven nebulized inhalation treatment for severe cough; 2) One tablet of sulforaphane (4mg under 6 years old; 5mg over 6 years old) at bedtime every night after relief, together with oral dexloratadine (1.25mg under 6 years old; 2.5mg over 6 years old) for 8 to 12 weeks. 4. Prevention: 1) Go to public places as little as possible, wear a mask when you go out; 2) Try not to eat seafood and snacks; 3) Do not live in newly renovated houses, do not keep pets at home, do not keep flowers in bloom; 4) Eat lightly and drink more water.