Nose hairs have the function of condensing water vapor, keeping the nasal cavity moist, and blocking bacteria and foreign objects from entering the nasal cavity. If the nose hair is too long and itchy, you can use a shaver to shave it short. However, avoid plucking nasal hairs, which may cause dryness in the nasal cavity and also cause hair follicle infections and boils. There are no valves in the veins of the head and face, and inflammation next to or in the nasal cavity can cause retrograde infection to the skull through the facial vein, the medial canthus vein, and the ophthalmic vein, resulting in thrombotic cavernous sinus phlebitis, which can cause generalized fever and headache in mild cases and can be life-threatening in severe cases. If the nose itches even after the nasal hair is shaved, it may be caused by allergic diseases, you can take oral anti-allergy drugs such as loratadine.