A sinus infection, also called sinusitis, occurs when the tissue lining your sinuses becomes inflamed and swollen. Sinus infections often develop after a cold or viral upper respiratory infection, but allergies can also contribute by causing ongoing inflammation and blocked sinus drainage.
Knowing the signs of a sinus infection can help you determine when it's time to seek medical care.
Common Symptoms of a Sinus Infection
Sinus infections can cause a variety of symptoms, including:
- Nasal congestion or a blocked nose
- Thick yellow or green nasal discharge
- Facial pressure or pain, especially around the cheeks, eyes, forehead, or nose
- Headache or a feeling of pressure in the head
- Pain that worsens when bending forward
- Postnasal drip
- Persistent cough, especially at night
- Sore throat caused by drainage
- Reduced sense of smell or taste
- Fatigue or feeling generally unwell
- Bad breath (halitosis)
- Fever, which may occur with some bacterial sinus infections
Symptoms may affect one or both sides of the face and can range from mild to severe.
Is It a Sinus Infection or Allergies?
Because allergies and sinus infections share many of the same symptoms, it can be difficult to tell the difference.
Allergies typically cause:
- Clear, watery nasal drainage
- Sneezing
- Itchy eyes, nose, or throat
- Symptoms that occur during certain seasons or after exposure to allergens
Sinus infections are more likely to cause:
- Thick yellow or green nasal drainage
- Facial pain or pressure
- Fever (in some cases)
- Symptoms that persist beyond 10 days or worsen after initially improving
In some people, untreated allergies can increase the risk of developing recurrent or chronic sinus infections.
What Causes a Sinus Infection?
Sinus infections may be caused by:
- Viral infections, such as the common cold
- Bacterial infections
- Seasonal or year-round allergies
- Nasal polyps
- Structural problems, such as a deviated septum
An evaluation can help determine the underlying cause of recurring sinus symptoms.
When Should You See a Doctor?
Most viral sinus infections improve on their own within 7 to 10 days. However, you should seek medical evaluation if:
- Symptoms last longer than 10 days without improving
- Symptoms improve but then become worse again
- You have severe facial pain or swelling
- You develop a high fever
- You experience vision changes or swelling around the eyes
- You have frequent or recurring sinus infections
How Are Sinus Infections Treated?
Treatment depends on the underlying cause of your symptoms. Your healthcare provider may recommend:
- Saline nasal irrigation
- Nasal corticosteroid sprays
- Decongestants when appropriate
- Antibiotics for certain bacterial sinus infections
- Allergy evaluation and treatment if allergies are contributing to recurrent sinus problems
If you experience frequent sinus infections or ongoing nasal congestion, an allergy evaluation may help identify underlying allergic triggers. Treating allergies can often reduce inflammation, improve sinus drainage, and decrease the likelihood of future sinus infections.