The cause of cough in the later stages of a cold may be related to viral-induced inflammatory mediators leading to hypersensitivity or damage to the mucous membranes of the respiratory tract, or it may be related to post-infectious cough. Colds are a type of upper respiratory infection, caused by viral infections, and may present with a cough, dry, itchy or burning throat. These symptoms may be associated with a state of hypersensitivity of afferent nerves in the upper respiratory tract due to virus-induced inflammatory mediators. Secondly pathogenic infections that result in damage to the mucous membranes of the respiratory tract can also produce cough symptoms. As colds are self-limiting, symptoms usually resolve in 5-7 days. When the acute phase of respiratory infection disappears, the cough is still prolonged, lasting more than 3 weeks, generally need to consider the post-infectious cough, which is related to cold-induced inflammation of the respiratory tract has not been fully recovered. Cough can be caused by many reasons, such as repeated coughing, it is recommended to consult a doctor in a timely manner, a clear diagnosis, and comply with the doctor’s instructions for medication, so as not to delay the condition.