Many different disease processes can produce the feeling of nasal obstruction, and therefore understanding the underlying cause will determine treatment. A few potential causes for nasal obstruction are highlighted below:

• Allergic rhinitis
  In many people, the immune system can develop a hypersensitive reaction to benign particles in the air we breathe. These particles, called allergens, can consist of pollen, mold, dust mites, animal dander, and many other substances. When present in high amounts within the nose, allergens cause histamine release throughout the lining of the nasal passages, resulting in swelling and clear mucous production. This ultimately makes it more difficult to breathe.


• Sinusitis
  Often preceded by a viral infection, sinusitis occurs when the small passages that connect your sinuses to the nasal cavity become blocked and allow bacteria cause an infection. The lining of the nose becomes inflamed and swell as your body fights the infection. This can cause a chain reaction in the are which then results in other sinus drainage pathways to get congested and clogged up as well. Sinusitis can be a temporary, self limiting infection, or persist long term as chronic inflammatory condition.


• Nasal polyps
  Nasal polyps are benign tissue growths from the mucosa that lines your nasal and sinus passages, and typically have the appearance of peeled grapes. Some nasal polyps are small and cause no symptoms, while others can take up a significant amount of space and block the normal drainage pathways of your sinuses. This can lead to nasal congestion and persistent sinus infections.


• Anatomic abnormality
  Structural irregularities in the nose can physically block the flow of air while breathing. A deviated septum, enlargement of the nasal turbinates, nasal valve collapse are just a few examples of anatomic abnormalities that can produce symptoms of nasal obstruction.


• Deviated septum
  The nasal septum is the wall that separates the right and left side of the nasal passage of the nose, and consists of cartilage, bone, and mucosa. A deviated septum is defined as a nasal septum that bends, or is displaced, to one or both sides of the nose. This can cause the nasal airway to become narrowed.


• Turbinate hypertrophy
  The turbinates are long round structures that hang from the sides of the nasal passage that help warm, humidify, and cleanse the air we breathe. It these structures are too large (or hypertrophied), they can prevent air from properly flowing through the nose. Turbinate hypertrophy is often treated alongside with a deviated septum and always begins with topical sprays. A turbinoplasty, or surgery to reduce the size of the turbinates, is performed when medical treatment fails.


• Nasal valve collapse
  The tip of the nose is a structure formed by different cartilages that help keep the nose open during breathing. These cartilages are synonymous with the beams that help support building. If they become weakened either from an injury or previous nasal surgery, they lose the ability to keep the nose open when taking a breathe. The negative pressure sucks all sides of the nose in preventing anymore air from getting in. This has the same effect of pinching your nose. Nasal valve collapse often requires either a functional rhinoplasty or advanced treatments to help stiffen the nasal side walls.


• Neoplasm
  On the more rarer occasion, a large neoplasm (tumor) growing within the nasal cavity can physically block air from flowing through the nose. Neoplasms will tend to cause one sided nasal obstruction, and often present with other symptoms such as epistaxis (nosebleeds) or facial pressure/pain. Neoplasms will always require complete surgical excision as baseline treatment.