Cold and flu clear nasal mucus into pus nasal mucus mainly consider cold and flu viral infection secondary bacterial infection, can be given local treatment and anti-infection treatment. 1. Local treatment: commonly used nasal decongestants, such as hydroxymetazoline hydrochloride nasal drops, ephedrine nasal drops. Decongestants have the effect of contracting nasal mucosa, reducing nasal congestion and improving drainage, but such drugs should not be used continuously for more than 7 days, otherwise it is easy to lead to drug rhinitis. 2. Anti-infection treatment: Colds are usually caused by viral infections, manifested by nasal congestion, runny nose and other symptoms. If the clear nasal discharge turns into purulent nasal discharge, it suggests that there is a combination of bacterial infection. You can use antibiotics such as amoxicillin or azithromycin under the guidance of a doctor to fight infection. The presence of purulent nasal discharge is not necessarily related to colds, but may be caused by acute sinusitis and other diseases. If the symptoms do not improve or aggravate, it is recommended to consult a doctor in a timely manner, improve the examination, clarify the cause of the disease, and under the guidance of the doctor reasonable treatment, so as to avoid delaying the condition.