When a cough does not improve after two months of medication, the cause of the cough needs to be identified and treated. Clinically, CT of both lungs as well as lung function and even allergens can be tested to consider that the cough may be due to allergic cough. Clearly it is cough variant asthma, which is a specific type of bronchial asthma, and medications that relax the bronchial smooth muscle should be given, such as a choice of salbutamol, terbutaline, ipratropium bromide, etc., administered by nebulized inhalation or orally. Glucocorticoids, such as dexamethasone, methylprednisolone, prednisone, budesonide, etc., can also be given by nebulization or intravenous drip or oral administration. Anti-allergic drugs such as paracetamol, cetirizine, loratadine, ketotifen, etc., as well as compound preparations such as compound methocarbamol capsules, and intravenous aminophylline, if necessary, can be given to open the airway and reduce or even eliminate the cough. The cough will disappear gradually if allergens are identified and contact with allergies is avoided.