Overview of Sinusitis

Sinusitis is the inflammation or swelling of the sinuses that surround your nose, usually caused by a viral or bacterial infection. It is a common condition that often clears up without medical treatment. However, if your symptoms last for more than 7–10 days or if you experience a fever or a bad headache, you should schedule an appointment with your general practitioner (doctor).

What are Sinuses?

Sinuses are small, air-filled spaces located in your facial bones that are connected to your nasal cavity or the inside of your nose. Since they surround the nose, they are also known as paranasal sinuses.

Everyone has 4 pairs of sinuses: behind your forehead (frontal sinuses), cheeks (maxillary sinuses), nasal bones (sphenoid sinuses) and between your eyes (ethmoid sinuses).

The main function of these sinuses is to produce mucus, a thin, watery fluid that flows freely from your sinuses into your nasal cavity. This layer of mucus acts as a trap for dust, germs, and other particles in the air. It also contains antibodies and bacteria-killing enzymes that help fight infections.

What is Sinusitis?

Sinusitis, or sinus infection, occurs when excess mucus builds up in your sinuses.

The presence of bacteria, viruses or allergens in your sinuses can cause too much mucus to form, blocking the tiny openings of your sinuses. As a result, mucus is unable to flow through these openings into the nasal cavity. The buildup of mucus in the sinuses encourages germs to grow, leading to a sinus infection.

Most sinus infections can clear up on its own without treatment. However, if your symptoms worsen after 5 days or persist longer than 10 days, a bacterial infection may be present and you should consult your doctor. Occasionally, an infected tooth or fungal infection can also cause sinusitis.

Types of Sinusitis

Sinusitis can be classified into 3 different types based on its duration.

• Acute Sinusitis.Acute sinusitis is the most common type. A viral infection can cause symptoms that last between 1-2 weeks. In the case of bacterial infection, acute sinusitis can last up to 4 weeks.
• Subacute Sinusitis.Subacute sinusitis symptoms last longer than acute sinusitis symptoms, between 4-12 weeks. This type commonly occurs with bacterial infections or seasonal allergies.
• Chronic Sinusitis.Chronic sinusitis symptoms persist for more than 12 weeks and may continually return. This type is usually caused by bacterial infections, persistent allergies or structural nasal problems. It may also require more invasive treatment such as surgery.

Symptoms of Sinusitis

Symptoms of sinusitis vary according to the length and severity of the sinus infection.

In general, if you have 2 or more of the following symptoms accompanied by thick, green or yellow nasal discharge, your doctor may diagnose you with sinusitis.

Common symptoms include:

• Blocked or runny nose
• Postnasal drip or mucus running down the back of your throat causing irritation
• Thick nasal discharge
• Reduced sense of smell and taste
• Cough or congestion
• Pain and tenderness around your cheeks, eyes or forehead

Other symptoms may include:

• Pain in the upper jaw and/or teeth
• Bad breath
• Fatigue
• Fever
• Headaches
• Nausea

When should you see your doctor?

If your symptoms are mild and improving, you don’t usually need to see your doctor and can look after yourself at home. However, see your doctor if:

• Your symptoms are severe or getting worse, e.g.,
  • Fever (above 39 degree celsius)
  • Swelling around your eyes or forehead
  • Severe headache or facial pain that does not resolve with over-the-counter (OTC) drugs
  • Confusion
  • Double vision or other visual disturbances
  • Stiff neck
• Your symptoms persist after 7-10 days
• Your symptoms continue after taking antibiotics prescribed by your doctor
• You experience episodes of sinusitis frequently

Common symptoms include:

The following may increase your risk of developing sinusitis:

• Previous respiratory tract infections such as the common cold
• Allergic reaction to substances such as dust, pollen or animal hair
• Deviated nasal septum: a crooked septum (the wall between the nostrils) may restrict or block sinus passages, making the symptoms of sinusitis worse
• Nasal polyps: small growths that can block nasal cavity or sinuses
• Asthma
• Dental infections
• Immune system disorders or autoimmune diseases such as HIV/AIDS or cystic fibrosis that can lead to nasal blockage
• Allergic rhinitis (hay fever)
• Smoking
• Regular exposure to pollutants such as carbon monoxide, nitrogen oxide, sulphur dioxide or secondhand cigarette smoke