I would recommend to start using Viferon suppositories, which have an antiviral effect, since a runny nose is most often a symptom of a respiratory viral infection. The drug inhibits the multiplication of viruses, protects healthy cells from infection.
The second omment is mandatory hygiene of the nasal cavity - instill vasoconstrictor drops, then after 5 minutes rinse with sea water or a warm solution of furacillin, and then drip sialor.
As for inhalations, then on a nebulizer with miramistin and saline - they have an anti-inflammatory effect.
I heard different versions