What Is Sinusitis (Sinus Infection)?

That feeling of uncomfortable pressure behind your face, along with a stuffy nose and other cold-like symptoms? It might be sinusitis, more commonly referred to as a sinus infection. Sinusitis develops when the mucous lining of the sinuses—the pockets of air behind your facial structure—become inflamed, possibly due to a virus, bacterium, fungus or allergen.

Sinusitis is common. It's estimated that almost 30 million cases of sinusitis are diagnosed in U.S. adults each year. While many of those sinusitis episodes go away on their own within a month, a healthcare provider can help detect the underlying cause and recommend treatment options for any lingering infections.

Types of Sinusitis

To help diagnose sinusitis and determine the best course of action for treatment, medical experts typically classify the illness by the following types:

• Acute sinusitis: Symptoms usually last four weeks or less.
• Subacute sinusitis: Symptoms last between four and 12 weeks.
• Chronic sinusitis: Symptoms last for 12 weeks or more.
• Recurrent sinusitis: If you have several sinusitis infections per year—without having any symptoms in between them—the sinusitis is usually considered to be recurrent (happening over and over).

Sinusitis Symptoms

Having a sinus infection may feel similar to a having a cold—but worse. Common sinusitis symptoms include:

• Stuffy nose
• Runny nose
• Facial pain and pressure
• Headache
• Post-nasal drip
• Fever
• Sore throat
• Bad breath
• Fatigue
• Weakness
• Loss of taste and smell
• Yellow or green nasal mucous
• Thick nasal drainage
• Tooth pain

What Causes a Sinus Infection?

A wide range of factors can cause sinusitis, which can make it confusing to figure out the underlying cause. Here's how some of the most common causes can be grouped:

• Infections: A virus, bacterium, or even a fungus can cause sinusitis. Most commonly, it is a virus.
• Inflammation: Exposure to an allergen like dust, smoke, dander, or mold can cause inflammation in the area and trigger sinusitis.
• Chronic illness: A condition that affects the airways, like asthma, can lead to the development of sinusitis.
• Anatomy: Physical obstructions in the nose like nasal polyps (noncancerous tissue growths) or a deviated septum (a misplaced wall between your nasal passages) can make it more likely for sinusitis to develop.

Risk Factors

Having certain risks factors can up your chances of developing a sinus infection. This includes circumstances like:

• Previously having a cold
• Experiencing seasonal allergies
• Smoking or being exposed to secondhand smoke
• Having a structural issue with the sinuses
• Taking medications that weaken the immune system

Diagnosis

A healthcare provider will perform a physical exam and ask about your symptoms and medical history to help make a sinusitis diagnosis. 

During this appointment, you can expect your ears, nose, and throat to be examined for signs of inflammation, blockage, or infection. In doing this, your healthcare provider ma be looking for redness, swollen nasal tissues, a swollen face that's tender to the touch, discolored nasal mucus, and bad breath.

From there, other tests may be ordered if needed, such as:

• Nasal endoscopy, where a thin tube inserted into your nose allows a closer look at the sinus area
• Imaging such as a CT scan, which can help pinpoint any structural or deep-rooted issues
• Tissue samples, which involves taking a small sample from your nose or sinuses in cases where a fungal or bacterial infection is suspected
• Allergy testing to narrow down a potential allergen behind the sinusitis

Treatments for Sinusitis

The treatment approach healthcare providers recommend will largely depend on the type of sinusitis you have.

Many cases of acute sinusitis will resolve themselves within 10 days or so. Your healthcare provider might suggest what's known as watchful waiting—essentially, observing your symptoms for a couple of days to see if your body can fight off the sinus infection without prescribed treatment.

Some cases of sinusitis will need treatment. In addition to clearing the infection, the goal with treatment is to minimize any uncomfortable symptoms you're experiencing in the meantime.

OTC and Home Remedies

People diagnosed with acute sinusitis are often good candidates for over-the-counter (OTC) and home remedies to ease symptoms. Some options include:

• Nasal decongestant
• Pain reliever
• Warm compresses for sinus pressure
• Saline nasal spray
• Steam from a hot shower
• Cough or cold medications
• Plenty of fluids
• Lots of rest

Prescription Medications

In more severe or chronic sinusitis cases, treatment options might involve prescription medications, such as:

• Corticosteroid nasal spray
• Oral steroids
• Antihistamines
• Anti-fungal medications
• Antibiotics (for a bacterial infection only)

If treatment doesn't seem to be working, at some point your healthcare provider might consider a referral to an ENT (ear, nose, and throat specialist) or recommend a surgical procedure to help clear any blockages in extreme cases.

Preventing Sinus Infections

There's no surefire way to completely avoid sinusitis, but there are some steps you can take to prevent the likelihood of an infection developing. Experts recommend tips like:

• Washing your hands frequently
• Keeping allergies, asthma, and other underlying conditions under control
• Staying away from people who may be sick with a respiratory illness
• Avoiding smoking and secondhand smoke exposure
• Staying hydrated
• Eating a balanced diet
• Exercising routinely
• Using a humidifier, if needed
• Receiving recommend vaccines, such as a flu shot

Co-Occurring Conditions

Sinusitis may not appear alongside any other condition. Depending on the underlying cause, though, there might be a condition happening alongside the sinus infection. Conditions that can happen alongside sinusitis include allergies, asthma, and nasal polyps.

Sinusitis might also affect sleep. It's believed that the symptoms of a chronic sinusitis can make it hard to fall and stay asleep, leading to fatigue during the day. The lack of good-quality sleep can also lead to depression, a poorer quality of life, and worsened cognitive function.

There is also some evidence to suggest that chronic sinusitis is associated with obstructive sleep apnea, when breathing is temporarily cut off during sleep due to narrowed airway. The research is inconsistent, though.

A Quick Review

Sinusitis is common. While symptoms can be annoying, the sinus infection usually clears up on its own within a month. If a sinus infection lasts longer or continues to crop up, a healthcare provider can help determine what the cause is and recommended an appropriate treatment plan.

Even if you have acute sinusitis, there are still certain signs you should keep an eye out for that might signal you should visit a healthcare provider. Those signs include:

• A high fever
• Symptoms that have lasted more than 10 days
• Symptoms that are getting worse or are not getting any better
• A severe headache along with your symptoms
• Vision changes, double vision, or swelling around the eyes

Even if a healthcare provider determines you don't need any prescribed medication, ask them about any OTC medications you can take to make yourself feel better as the sinusitis clears. The pain and pressure may be relieved with the help of a decongestant or even a warm compress or hot shower.