Sinusitis (Sinus Infection): Symptoms, Diagnosis, Treatment, Prevention

Sinusitis is an inflammation of the lining of the nasal sinuses. It is a common condition typically caused by a viral infection and improves within a few weeks. The sinuses are small, air-filled cavities behind the forehead and cheekbones.

The mucus generated by your sinuses generally drains into your nose via small channels. In sinusitis, the sinus linings are inflamed and cause the channels to become blocked.

What are sinuses?

There are four pairs of sinuses:

  • Sphenoidal sinuses: Located deep in the skulls, behind your eyes
  • Frontal sinuses: Located in the forehead
  • Ethmoidal sinuses: Located behind the bridge of the nose, between your eyes
  • Maxillary sinuses: Located in both cheeks

The sinuses produce secretion known as mucus, which traps germs while retaining the inner moisture. When the sinuses get filled, bacteria can grow and cause an infection known as bacterial sinusitis. The maxillary sinus is most commonly affected.

What are the causes of sinusitis?

Sinusitis is commonly caused by a viral infection that spreads to the sinuses causing blockage of the narrow sinuses.

Bacterial sinusitis is much less prevalent, occurring in about 0.5% to 2% of cases, and is usually a complication of viral sinusitis.

What are the symptoms of sinusitis?

Symptoms of sinusitis include:

  • Pain, tenderness, and swelling around your forehead, eyes, and cheeks
  • Reduced sense of smell
  • Blocked nose
  • Thick white, yellow, or green discharge from your nose
  • Fever
  • Bad breath
  • Toothache
  • Cough
  • Ear pressure
  • Tiredness

Sinusitis in children can cause irritability, mouth breathing, and feeding difficulties. Their speech may sound nasal (similar to a blocked nose).

Usually, symptoms begin to improve after 7 to 10 days.

What are the types of sinusitis?

Sinusitis can generally be classified into three types. These are:

  1. Acute sinusitis: Symptoms last less than 4 weeks
  2. Subacute sinusitis: Symptoms last 4 to 12 weeks
  3. Chronic sinusitis: Symptoms last for more than 12 weeks

For recurrent acute sinusitis, there are 2 to 4 episodes happening in a year with at least 8 weeks between episodes.

What are the risk factors for sinusitis?

Several factors increase the risk of developing a sinus infection which includes:

  • Weakened immune system
  • Structural abnormality to the nose, such as deviated septum
  • History of allergies
  • Dental infection
  • Smoking tobacco
  • Nasal polyps
  • Dental infection
  • Cystic fibrosis
  • Upper respiratory tract infection
  • Smoking or second-hand smoking
  • Hay fever
  • Seasonal allergies

Is sinusitis contagious?

Viral sinusitis is contagious and can spread from one person to another when the infected individual coughs or sneezes.

Initially, it is difficult to determine if a sinus infection is viral or bacterial. Studies indicate that the duration of symptoms is not always sufficient to differentiate between viral and bacterial sinusitis, even if they last longer than 7 to 10 days.

It may be bacterial sinusitis if symptoms last longer than 10 days or worsen again within the first week ("double worsening").

How is sinusitis diagnosed?

Your doctor would first question your general health and symptoms and conduct a thorough physical examination. Sinusitis can usually be diagnosed based on symptoms and examination of the nose.

Some of the other methods of diagnosis include:

  • Nasal endoscopy: A thin, flexible tube with a light and video camera at one end (endoscope) is inserted deep into the nose. On a monitor, images captured by an endoscope are presented.
  • Allergy test: Your doctor may also recommend an allergy skin test to determine if the sinusitis is caused by allergens.
  • Imaging: Imaging tests are used to view the details of your sinuses. These include magnetic resonance imaging (MRI) and computed tomography (CT).

What are the treatment options for sinusitis?

The primary treatment for sinusitis is symptom relief, as antibiotics are only required in a small percentage of people. Sinusitis often improves without antibiotics as it is usually caused by a virus.

The following are some of the treatment options for sinusitis:

  • Nasal irrigation with saline solution
  • Pain medication such as acetaminophen and ibuprofen
  • Nasal steroids
  • Nasal anticholinergics such as Ipratropium bromide
  • Oral decongestants such as pseudoephedrine and phenylephrine
  • Nasal decongestant sprays such as oxymetazoline and phenylephrine
  • Oral antihistamines such as diphenhydramine

If your symptoms worsen, your doctor may start you on antibiotic treatment. The commonly prescribed antibiotic is amoxicillin.

In some instances, if a patient is not responding to medications, surgery may be recommended. A surgical procedure known as Functional Endoscopic Sinus (FESS) is done to improve the drainage of mucous from your sinuses.

How to manage sinusitis at home?

If your symptoms are mild, you can try some of the following home remedies to help you feel better.

  • Over-the-counter pain medication such as paracetamol
  • Decongestant or saine nasal spray
  • Steam inhalation.
  • Place a warm compress over the forehead to relieve sinus pressure

What are the prevention tips for sinusitis?

  • Practice good hand hygiene
  • Take the recommended vaccines such as influenza and pneumococcal vaccine
  • Avoid smoking and second-hand smoking
  • Avoid close contact with people who have respiratory infections
  • Keep away from allergens
  • Use a humidifier at home

Book an appointment at Pantai Hospitals

If the home remedies do not work and your sinusitis worsens, speak to your doctor immediately. The caring team of healthcare professionals are available for consultation and to provide the best care.

Get in touch with us to book an appointment with Ear, Nose & Throat (ENT) specialists at Pantai Hospitals today if you have any concerns or questions about sinusitis.

Pantai Hospitals have been accredited by the Malaysian Society for Quality in Health (MSQH) for its commitment to patient safety and service quality.


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