Coughing in the late stage of a cold can be caused by backflow of nasal mucus or inflammation of the throat, or by other factors. 1. Reflux of nasal mucus: When a patient has a cold, a series of symptoms such as sneezing, runny nose, etc. If the nasal mucus flows backward, it will stimulate the patient and cause a cough. 2. Inflammation of the throat: Colds are essentially upper respiratory tract infections, and the main upper respiratory tract organs include the throat, nose and pharynx. If the patient’s upper respiratory tract is infected with bacteria or viruses, it can cause inflammation of the throat, which can lead to coughing. 3. Other factors: When the patient has a cold, it can also cause other complications such as pneumonia and bronchitis, which may cause the patient to cough. It is important to note that if the patient has a cough after a cold, he should go to the hospital in a timely manner, and actively treat it to avoid delaying his condition.