Cold has been runny nose, sneezing is a very common symptom, the root cause is caused by the infection of the virus, but also to consider the possibility of allergic rhinitis, as follows: 1, caused by the infection of the virus: the virus in the upper respiratory tract reproduction, can cause clinical symptoms of upper respiratory tract infection, such as can cause acute inflammatory reaction in the nasal cavity, will stimulate the secretion of glands in the nasal cavity, resulting in symptoms such as runny nose and sneezing 2, the presence of allergic rhinitis: if the symptoms of runny nose and sneezing for more than a week, we should consider the possibility of allergic rhinitis. If the runny nose and sneezing are caused by a cold, they are self-limiting and last for about a week. Therefore, if you have a runny nose and sneezing all the time, you can use antihistamines to relieve it, such as cetirizine hydrochloride or loratadine, or you can use nasal decongestants, such as naphthazoline hydrochloride nasal drops or selorazoline hydrochloride nasal drops.