Take or leave,if there is yellow or green mucus it's possible it's an infection.Hydrosol silver nose spray help many in my area of the country.You have lots of pollution in your area.Many people use Xlear nasal spray twice a day. Spray, wait a minute or two,and spray again. Morning and evening. It contains xylitol, which can kill bad bacterias. Is it on the left side.Most are, that I have come across.Good luck!