Colds with dry cough and no phlegm are mainly caused by viral infections. Colds are caused by viral infections, commonly known as “colds”, which are viral infections of the upper respiratory tract. The most common virus in the common cold is rhinovirus, and other viruses include parainfluenza virus, respiratory syncytial virus, echovirus, coxsackievirus, and so on. There are also influenza viruses that cause the common cold, which usually have milder nasal symptoms and more severe symptoms such as fever and malaise. Triggers of colds include seasonal changes, crowded environments, malnutrition, stress, overexertion, and immunocompromise. When the body or local defenses of the respiratory tract are lowered, viruses previously present in the upper respiratory tract or invading from outside multiply rapidly, causing the disease. Colds may induce cough variant asthma, cardiac insufficiency pulmonary stasis, etc., or combined with bronchitis, etc., can also lead to a dry cough, it is recommended to go to the hospital in time, improve the examination to clarify the cause of the disease, and then give targeted treatment or therapy.