Sinus congestion is experienced as an inflammation of the cavities within the passages of the nose. Nasal allergies, or allergic rhinitis, is a fairly common condition and affects about one in five adults.
Sinuses are hollow air spaces in the skull that are connected to the nasal passages. When allergies cause the mucous membranes to swell, the inflamed tissue may block off the sinuses. This stops them from draining and traps mucus and air inside.
Allergy symptoms often mimic those of a cold. They can include sinus headaches, facial tenderness, pressure in the sinuses, ears and teeth, sore throat and cloudy nasal or postnasal drainage.
Allergies are generally triggered by sinus sensitivity towards things in your environment or to certain foods you eat. However, sinus problems may also be a result of physical deformities, such as a deviated septum.
The nasal septum is the thin wall of bone and cartilage that separates your two nasal passages. Usually it is in the centre of your nose, but in some people the nasal septum is off to the side, making one nasal passage smaller than the other. This can be caused by genetics or an injury. Some people also have narrow sinuses, creating a smaller space for drainage.