The following conditions are often associated with increased nasal drainage. Also, it would not be unusual to have more than one factor involved in a particular individual.
The following may cause an increase in thin secretions:
- viruses
- allergies
- cold temperatures
- certain foods or spices
- pregnancy or hormonal changes
- drug side-effects (particularly high blood pressure medications)
- structural problems (deviated septum, large turbinates)
- vasomotor rhinitis (an abnormal regulatory problem with the nose)
Decreasing the fluid content of the mucus usually thickens the secretions leading to the impression of increased mucus. The following may cause thickened secretions:
- Low humidity
- Sinus or nasal infections
- Foreign bodies: (especially if the drainage is from one side)
- Environmental irritants: (tobacco smoke, smog)
- Structural problems: (deviated septum, enlarged turbinates, enlarged adenoids)
- Advanced age: mucus membrane lining the nose can shrink with age leading to a reduced volume of secretions that are thicker
- Hormonal problems
- Drug side-effects: (antihistamines)