Nasal mucus comes from the capillaries inside the nasal cavity, or inside the sinuses. It is possible that the increase is due to cold combined with upper respiratory tract infection and bacterial infection, which increases the permeability of blood vessels and increases nasal mucus. In addition, chronic rhinitis or acute attack of sinusitis, combined with infection, leads to an increase. Therefore, it is better to go to the hospital for local examination of the nose to rule out other causes of increased nasal discharge if there is a lot of nasal discharge.