What is sinusitis?

Sinusitis refers to the inflammation of the sinuses. The sinuses are hollow areas in the facial bones around the nasal passage which are normally  filled with air. All these sinuses are lined with mucus membranes. An infection or an allergy in the mucus membrane may result in swelling and inflammation of the sinuses. Due to this mucus might not be able to drain out and might build up.

Where are the sinuses located?

There are four sets of sinus cavities. The different locations of the paranasal sinuses include :

  • Maxillary, inflammation of which affects the maxillary (cheek) area
  • Frontal, inflammation of which affects the front of the face (above the eyes)
  • Ethmoid, inflammation of which affects the area behind the eyes
  • Sphenoid, inflammation of which affects the area behind the eyes and top of the head

What are the types of sinusitis?

Sinusitis can be of two types:

  • Acute sinusitis which completely resolves in less than a month. A viral infection may prompt colonization of bacteria in the sinus. The sinus may get blocked and a vacuum may result from swelling of the mucus membrane. As a result, the fluid from the mucous membrane is unable to drain and it fills the sinus. It then serves as a medium for bacteria.
  • Chronic sinusitis which persists for more than 3 months. Chronic sinusitis may result from bacterial infection, pollution, dental infection or fungal infections (mostly in patients with a weak immune system).

What are the symptoms of sinusitis?

Acute and chronic sinusitis cause similar symptoms, which may include the following:

  • Runny nose
  • Yellow-green mucus
  • Pressure and pain in the face
  • Blocked nose
  • Reduced sense of smell
  • Bad odor which only the patient may notice
  • Cough with phlegm
  • Redness and swelling of the sinus
  • Facial discomfort or pain and sometimes headaches
  • Fever and chills (in case of an infection beyond the sinuses)

What causes sinusitis?

Causes of sinusitis may include the following:

  • Viral infection can cause acute sinusitis.
  • Bacterial or fungal infection may cause chronic sinusitis.
  • Allergic reactions may also result in inflammation of the mucus membranes of sinus.
  • A bent nasal septum (the wall between the nostrils) may partially block a sinus passage.
  • Growth of tissues like nasal polyps or tumors may block the nasal passages or sinuses.
  • Tooth infection may also cause acute sinusitis in some cases.
  • Infections (viral, bacterial or fungal) in the respiratory tract can inflame the sinus membranes and block mucus drainage.
  • Presence of some medical conditions (cystic fibrosis, HIV, or gastroesophageal reflux disease) increase the risk of developing an infection.

How is sinusitis treated?

Several conservative measures are taken to improve drainage and to control infection. Steam inhalation, keeping warm, wet towels over the affected sinuses, and drinking hot fluids help in clearing nasal congestion and promoting drainage. However, medication is usually needed as well and sometimes even surgical intervention.


  • Antibiotics (e.g., amoxicillin, trimethoprim/sulfamethoxazole, erythromycin, cefuroxime, moxifloxacin) are given for 10 to 14 days. However, moxifloxacin is not recommended in case of children as it may cause problems with bones and joints in children.
  • Vasoconstrictors (phenylephrine) are recommended in some cases.


Surgical procedures are performed for patients who do not respond to antibiotic therapy. Procedures like maxillary sinusotomy, sphenoid sinusotomy, or ethmoidectomy improve ventilation and drainage and remove the infected mucus and swollen or enlarged part of the mucous membrane. These procedures are usually done through the nose either with the help of an endoscope or computer-aided machines. This minimizes the risk of injury to surrounding structures like the eye and brain.


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