What Causes Sinusitis?

Sinusitis, also known as a sinus infection, occurs when the tissues lining the sinuses become inflamed and swollen. This inflammation can block the sinus openings, leading to a buildup of mucus and air inside the sinuses. Several factors can contribute to the development of sinusitis:

  • Viral Infections: The majority of sinusitis cases are caused by viral infections, such as the common cold or influenza (flu). These viruses can inflame the sinus lining and lead to sinusitis.
  • Bacterial Infections: In some cases, sinusitis can be caused by bacterial infections, which may develop as a complication of a viral upper respiratory infection. Bacterial sinusitis tends to be more severe and may require antibiotics for treatment.
  • Allergies: Allergic reactions to airborne particles like pollen, dust mites, pet dander, and mold spores can cause inflammation in the sinus lining, leading to sinusitis.
  • Nasal Polyps: Nasal polyps are soft, noncancerous growths that can block the nasal passages and contribute to sinusitis.
  • Deviated Septum: A deviated nasal septum, a condition where the thin wall between the nostrils is shifted to one side, can obstruct the sinus openings and increase the risk of sinusitis.
  • Environmental Irritants: Exposure to irritants like cigarette smoke, chemical fumes, and air pollution can irritate the sinuses and lead to inflammation.
  • Immune System Disorders: Individuals with weakened immune systems or certain immune system disorders may be more susceptible to sinusitis.
  • Cystic Fibrosis: Cystic fibrosis is a genetic disorder that can lead to thick, sticky mucus production, which can block the sinuses.
  • Dental Infections: Infections in the upper teeth can sometimes spread to the sinuses, causing sinusitis.
  • Swimming or Diving: Recreational water activities can introduce harmful bacteria into the nasal passages, leading to sinus infections (often referred to as “swimmer’s sinusitis”).

Acute sinusitis usually lasts for a short duration (less than four weeks) and is often associated with cold-like symptoms. Chronic sinusitis, on the other hand, lasts longer (more than 12 weeks) and may involve persistent or recurring symptoms.

Treatment for sinusitis varies based on the underlying cause and severity of symptoms. It may include over-the-counter pain relievers, decongestants, nasal saline rinses, and in some cases, antibiotics for bacterial infections. Managing allergies and avoiding triggers can also help prevent sinusitis episodes. If sinusitis is chronic or recurrent, medical evaluation and management by a healthcare professional, such as an otolaryngologist (ear, nose, and throat specialist), may be necessary to identify and address underlying factors contributing to the condition.