The reason for the cold without fever and runny nose may be due to the increase of nasal secretion caused by the congestion and edema of the local mucous membrane of the nasal cavity due to viral infection. When a person with a cold is infected by a virus, the mucous membrane of the nose may show inflammatory congestion and edema as well as dilation of capillaries, and then the nasal secretion will increase, which will show the symptom of runny nose. Pseudoephedrine hydrochloride can be taken as a decongestant to reduce the production of nasal discharge. In addition, allergic rhinitis can also be characterized by runny nose without fever. Under the action of allergens, the nasal mucosa can be stimulated to produce allergic rhinitis, the nasal mucosa is obviously swollen, the mucus secretion is extremely exuberant, resulting in runny nose. It can be treated by taking antihistamines such as cetirizine. Cetirizine has a drowsy reaction to its use and drivers or pilots should be aware of this. If there is a recurrent cold without fever and runny nose, etc., you need to consult a doctor in time to clarify the cause of the disease, and then follow the doctor’s instructions for treatment.