The glands in your nose and throat produce up to two quarts of mucus a day. This is usually true even for a healthy person. Normally, this mucus is clear and thin and serves a useful role in keeping the mucus membranes clean and moist. Excessive secretions of mucus in response to inflammation or infection can cause a buildup of dried or thick mucus and create the feeling that mucus is dripping from the back of the nose into the throat. This sensation, called “post-nasal drip,” can be caused by these thick, draining mucus secretions or by other throat and swallowing conditions. Correct diagnosis is critical to developing a successful treatment plan.
Causes Of Mucus Secretions
- Viruses such as colds and flu
- Environmental airborne pollutants
- Environmental allergies
- Cold temperatures
- Bright lights
- Certain foods/spices
- Pregnancy, and other hormonal changes
- Various drugs (including birth control pills and some high blood pressure medications)
- Structural abnormalities (deviated or irregular nasal septum)
- Dryness due to climate or in heated buildings and homes
- Sinus infections
- Some food allergies or sensitivities (especially to dairy products)
If thin mucus secretions become thick, and turn green or yellow, it may be an indication that a bacterial sinus infection is developing.
Excess mucus secretions can cause hoarseness or coughing when they spill into the voice box (larynx) and breathing passages (trachea and bronchi). The latter would typically happen only with the elderly or in individuals with laryngeal functional problems. However, viral infections, pollutants, and allergens that irritate the lining of the nose and throat can also irritate the lining of the trachea and bronchi in the lungs. This often causes mucus to form in the chest a few days after it starts in the nose and sinuses, giving the impression that mucus is “flowing” from the nose down into the chest. Post-nasal drip can also cause a sore throat due to local irritation, throat clearing, and mouth breathing when the nose is also congested. Even without a sinus infection, the tonsils and other tissues in the throat may swell and become irritated with excessive post-nasal drip, especially if a viral infection is present.