Nasal hair Nasal hair Nasal hair or nose hair is the hair in the nose. Adult humans have hair in the interior nasal passage. Nasal hair functions include filtering foreign particles from entering the nasal cavity and collecting moisture. In support of the first function, the results of a 2010 study indicated that increased nasal hair density decreases development of asthma in those who have seasonal rhinitis, possibly due to an increased capacity of the faces to filter out pollen and other allergens. Nasal hair should not be confused with cilia of the nasal cavity, which are the microscopic cellular strands that,
Mucus mucus production in the upper respiratory tract is a symptom of many common ailments, such as the common cold. Nasal mucus may be removed by blowing the nose or by using nasal irrigation. Excess nasal mucus, as with a cold or allergies, due to vascular engorgement associated with vasodilation and increased capillary permeability caused by histamines, may be treated cautiously with decongestant medications. Thickening of mucus as a "rebound" effect following overuse of decongestants may produce nasal or sinus drainage problems and circumstances that promote infection. During cold, dry seasons, the mucus lining nasal passages tends to dry out, meaning