Sinuses act as air filters in your nose. They filter the air you breathe, smoke, pollution, including viruses and bacteria before the air gets into your lungs with the right temperature and humidification. Sinuses, when healthy, are filled with air all the time. But when they get inflamed, blocked and filled with fluid, that is the cue for the germs to enter and grow. There are a lot of factors that can block the sinuses. It can be a common cold, allergic rhinitis, smoke, allergies, nasal polyps, and misaligned septum which 80% of people have.

Sinusitis is experienced by almost everyone. Some have it that lasts a few weeks and some symptoms last for more than 4 months. The types of sinusitis depend on the symptoms and how long they stay with the patient.

Here they are :

Acute sinusitis - 2 - 4 weeks 

Subacute sinusitis - 4 - 12 weeks

Chronic sinusitis - 12 weeks and longer

Recurring sinusitis - symptoms recur several times a year