There are many diseases that can lead to chronic cough, including the following: 1. Cough variant asthma. Cough variant asthma can present with a persistent cough and the use of antibiotics is ineffective. If patients are diagnosed with cough variant asthma after pulmonary function and bronchodilator tests, they should avoid contact with allergy-prone substances, inhale Symbicort and Sulforaphane, and take oral montelukast sodium; 2. Gastroesophageal reflux disease can also cause chronic cough. 3. Cough can also occur with medications, such as captopril, in which case we need to stop the medication causing the cough.