Cough is a common symptom of whistling tract diseases, often occurring in the presence of upper and lower whistle infections, tuberculosis, lung cancer, and other diseases. In most cases, the symptoms of coughing due to an inhalation tract infection can gradually improve after antibiotic treatment, but sometimes the patient’s coughing symptoms are not reduced at all after treatment with multiple antibiotics and cough suppressants, and instead they are prolonged. Cough variant asthma (CVA), also known as cough asthma, used to be called allergic asthma, allergic bronchitis, allergic cough, cryptogenic asthma, and cough asthma. In 1972 Gluser first reported the disease and named it as variant asthma. Cough variant asthma is a specific type of asthma in which chronic cough is the main or only clinical manifestation. The Global Guidelines for the Management of Asthma (GINA) clearly state that cough variant asthma is a form of asthma that has the same pathophysiological changes as typical asthma, namely a sustained airway inflammatory response with airway hyperresponsiveness. Nakajima et al. found that the longer the duration of cough, the greater the likelihood that CVA would develop into classic asthma after 5 years of clinical observation, and one study showed that nearly 30% of patients with CVA would develop classic asthma within a few years. Almost all patients report that they have been coughing for more than a month, mostly in the early morning or during the day, in paroxysms, especially after exposure to cold air, cooking fumes, cigarettes and other irritants; there is no obvious shortness of breath or fever, and chest x-ray and routine blood tests are not significantly abnormal. The effect of antibiotic and cough suppressant treatment is not good. In the past, these patients were often misdiagnosed as “cold” or “bronchitis”. In recent years, with the development of medical science, scholars at home and abroad have discovered that these patients may suffer from cough variant asthma. Due to the persistent inflammatory metaplasia in their airways, the bronchial epithelium is swollen, making the excitation threshold of the subcutaneous stimulus receptors in the airways lower than normal, thus increasing their sensitivity to various external stimuli and causing coughing at the slightest stimulus. Some data show that the number of patients with allergic cough increases year by year in cities with significant industrialization and in developed coastal areas, indicating that the environment has a very obvious influence on allergic cough. Clinical characteristics of CVA: 1. chronic cough, often manifested as a chronic irritating dry cough, usually more intense, with nocturnal cough as its important feature; 2. may not be accompanied by wheezing symptoms typical of asthma; 3. triggers are mostly irritation of the whistle tract (e.g. smoke, cold air or allergens); 4. cough duration >2 weeks; 5. some patients have a family or personal history of allergic diseases; 6. routine pulmonary function tests are mostly are normal, while bronchial excitation tests can confirm the diagnosis. Other tests may also reveal increased sputum eosinophilia, increased serum eosinophil cationic protein (EcP) levels, and increased eosinophilia in bronchoalveolar lavage fluid (BALF), but they are mostly non-specific. If a patient is found to have the above symptoms, it is important not to seek medical advice or believe in folk remedies, but to go to a regular hospital for systematic and standardized diagnosis and treatment to avoid delaying the disease and causing more serious consequences. Since nearly 30% of CVA patients may develop into typical asthma within a few years, early diagnosis and treatment of CVA is particularly important. Therefore, patients who are diagnosed with CVA should receive standardized anti-asthma treatment as soon as possible.