What Is Sinusitis?

Medically Reviewed by Poonam Sachdev on November 05, 2023
12 min read

Sinusitis is an inflammation, or swelling, of the tissue lining the sinuses. Sinuses make mucus, which keeps the inside of your nose moist. That, in turn, helps protect against dust, allergens, and pollutants.

Healthy sinuses are filled with air. But when they become blocked and filled with fluid, germs can grow and cause an infection.

Conditions that can cause sinus blockage include:

  • The common cold
  • Allergic rhinitis, which is swelling of the lining of the nose caused by allergens
  • Small growths in the lining of the nose called nasal polyps
  • A deviated septum, which is when the nasal cavity is crooked

What are your sinuses?

Your sinuses are empty spaces in your skull. You have four pairs of sinuses for a total of eight. The pairs are found:

  • Above your eyes
  • Between your eyes
  • Behind your nose
  • Under your eyes, behind your cheeks

There are several different types of sinusitis. In many cases, your doctor will determine the type you have by how long you have had symptoms. Your type also depends on what caused your sinusitis. Let’s take a look.

Acute sinusitis

Acute sinusitis is typically caused by the common cold, a viral infection. You should feel better within 10 days, though symptoms could stick around as long as 4 weeks. You’ll experience the following symptoms:

  • Stuffy nose, or nasal congestion, that makes it tough to breathe through your nose.
  • Thick green or yellow mucus draining from your nose -- a runny nose -- or down the back of your throat, called postnasal drip.
  • Pain, pressure, swelling, and tenderness around your nasal passages that feels worse when you bend over.
  • You also may get a headache, have pressure in your ear, a cough, and other unpleasant symptoms.

Chronic sinusitis

Chronic sinusitis brings on the same unpleasant symptoms as acute sinusitis. But it lasts a whole lot longer. You won’t be diagnosed with chronic sinusitis until you’ve had symptoms for at least 3 months.

What causes it? That’s not always clear. There are many things that increase your risk, including:

  • Nasal polyps, or small growths inside your nose
  • Deviated nasal septum, in which the bone and cartilage that divides your nose gets pushed to one side, often due to an injury
  • Allergies
  • Recurring respiratory infections
  • Diseases that affect the immune system, such as cystic fibrosis and HIV

Subacute sinusitis

This type of sinusitis falls between acute and chronic. If your sinusitis lasts more than 4 weeks but less than 12 weeks, you will be diagnosed with subacute sinusitis. Your symptoms may not be as severe as those you would experience if you had acute sinusitis.

Recurrent sinusitis

It’s not uncommon to get the occasional bout of acute sinusitis. After all, it goes hand in hand with the common cold. But for some people, it keeps going away and coming back again. If you get acute sinusitis four or more times each year, you have what’s called recurrent sinusitis.

Some of the same risk factors for chronic sinusitis also up your chances of recurrent sinusitis, such as nasal polyps, deviated nasal septum, and other abnormalities that can occur in or around the sinuses. If you regularly inhale tobacco smoke or other irritants in the air, you may have a higher risk of recurrent sinusitis. Sinusitis also raises your odds of developing a bacterial infection, which in turn makes recurrent sinusitis more likely.

Fungal sinusitis

Fungi (the plural of fungus) are living organisms that include mold, mildew, and mushrooms. They come in all sizes. Tiny fungi can be breathed in. Sometimes, that causes a fungal infection in your sinuses. There are two main categories:

  • Invasive fungal sinusitis. These rare infections can spread to your eyes, brain, and elsewhere. They can be deadly.
  • Non-invasive fungal sinusitis. These infections are more common. They affect only your nose and sinus area.

The most common type of fungal sinusitis is called allergic fungal rhinosinusitis. It’s caused by an allergic reaction to fungi that have taken up residence in your nose. The symptoms are similar to other forms of sinusitis. But if you have a weakened immune system, the symptoms can be different and severe:

  • Changes in behavior and brain function (you may have trouble thinking clearly)
  • Skin color changes, turning very pale or black
  • Numbness in your face
  • Your eyeballs stick out, a condition called proptosis
  • Severe swelling in your eyes and cheeks
  • Changes in vision, including vision loss and blindness

Allergic sinusitis

Dust, pollen, smoke, and other environmental irritants that you breathe in can trigger sinusitis. The symptoms are mostly similar to symptoms of other types of sinusitis. But allergic sinusitis can cause a unique symptom: itchy nose, eyes, and throat. Symptoms can come and go with the seasons as the amount of allergens in the air change throughout the year.


Normally, a sinus infection doesn’t affect all four pairs of sinuses in your head; it only affects one or two. But sometimes, all four can become infected at once. This is known as pansinusitis.

Bacterial sinusitis vs. viral sinusitis

Both types of sinusitis are infections that cause similar symptoms. But they are not the same and are treated differently.

As mentioned above, most sinusitis is caused by the common cold, a virus. And there’s no cure for that viral infection. Instead, you have to wait until it goes away. The symptoms typically begin to fade after 5 days to a week.

A bacterial sinus infection, on the other hand, sticks around longer -- often a week to 10 days. You can treat the symptoms the same way you treat those of viral sinusitis. Unfortunately, your bacterial infection may get worse, not better, after 7 days. That’s when it’s time to see the doctor. You may need an antibiotic to kill the bacteria causing the infection. (Remember: Antibiotics do not work for viral infections like viral sinusitis.)

These two types of sinusitis do often travel together. You may start with a viral infection and pick up a bacterial infection a week or so later. Why? That initial infection makes it harder for your mucus to filter out threats to your health, including bacteria.

Sinusitis vs. sinus infection

These terms are commonly used interchangeably, but they refer to different things that often go hand in hand. Sinusitis, sometimes called rhinosinusitis, refers to inflammation or swelling the develops in your sinuses. A sinus infection, which 9 times out of 10 is caused by a virus, is usually the cause of that swelling. But you can have sinusitis without an infection. For example, allergies can cause inflammation and swelling in your sinuses.

Lots of people. About 35 million Americans have sinusitis at least once each year. It’s more likely if you have:

  • Swelling inside the nose like from a common cold
  • Blocked drainage ducts
  • Structural differences that narrow those ducts
  • Nasal polyps
  • Immune system deficiencies or medications that suppress the immune system

For children, things that can cause sinusitis include:

  • Allergies
  • Illnesses from other kids at day care or school
  • Pacifiers
  • Bottle drinking while lying on the back
  • Smoke in the environment

The main things that make sinusitis more likely for adults are infections and smoking.

You may have these symptoms for 12 weeks or more:

  • A feeling of congestion or fullness in your face
  • A nasal obstruction or nasal blockage
  • Pus in the nasal cavity
  • A fever
  • A runny nose or discolored postnasal drainage

You may also have headaches, bad breath, and tooth pain. You may feel tired a lot.

Lots of things can cause symptoms like these. You'll need to see your doctor to find out if you have sinusitis.

Sinusitis headache

When sinusitis causes a headache, you’ll feel a nonstop dull pain around the area of the affected sinuses. That means behind your eyes, in your cheekbones, in your forehead, or around the bridge of your nose. The pain from the headache gets worse if you move your head suddenly or if you bend over. Sudden temperature changes also can increase the pain. Other symptoms include:

  • Worse pain in the morning
  • Tenderness in your face

Bad news: that headache is likely to stick around until your sinus infection clears.

How long does sinusitis last?

In order to receive a diagnosis of chronic sinusitis, your symptoms must last at least 12 weeks, or 3 months. Unfortunately, you may experience symptoms for much longer. Some research has found that symptoms can linger for more than a decade. They may improve over time, but they don’t always go away completely.

Is sinusitis contagious?

Sinusitis itself cannot be spread from person to person, so it is not contagious. But the cause of your sinusitis likely is. Remember, most sinusitis is caused by the common cold, a viral infection. That virus can be spread through respiratory droplets, meaning what flies out of your nose and mouth when you sneeze and cough -- and even when you talk. Also, some bacterial infections that trigger sinusitis -- such as Streptococcus pneumoniae, which causes some forms of pneumonia, meningitis, and sepsis -- can spread during close contact or by touching a contaminated object.

While medicines can help, many cases of sinusitis go away on their own without any medical treatment. If you often get the condition, many of these same approaches will help you prevent it, too.

Your treatment will depend on a number of factors, such as what caused your sinusitis and how long it has lasted. For example, sinusitis caused by a bacterial infection may require antibiotics, though it’s not likely. If it’s a result of the common cold, over-the-counter medications and time may be all you need. But if it has gone on for longer than 3 months, meaning it’s chronic, treatment may be more complex. 

Sinusitis medication

  • Antibiotics. If your doctor thinks a bacterial infection is to blame, they may prescribe antibiotics. For acute sinusitis, you typically take them for 10-14 days. For chronic sinusitis, it might be longer. Antibiotics only help with bacterial infections. They won’t help if your sinusitis is caused by viruses or other problems. 
  • Painkillers. Many people with sinusitis take over-the-counter (OTC) pain medicines, like ibuprofen or acetaminophen, to ease discomfort. Follow the instructions on the label, and don't take them for more than 10 days. Check with your doctor to see which one is right for you.
  • Bioelectronic sinus device. This works by using microcurrents to stimulate nerve fibers in your sinuses. Sold over-the-counter, it helps reduce sinus inflammation, pain, and congestion. 
  • Decongestants. These meds lower the amount of mucus in the sinuses. Some are available as nasal sprays. Others are pills. If you use decongestant nasal sprays for more than 3 days, they may make you more congested. Follow the instructions on the label.
  • Allergy medicines. Many cases of sinusitis are due to uncontrolled allergies. If you've never been diagnosed with allergies, it might be worth doing some allergy testing to see if you have them. If you do, medication (like antihistamines) and avoiding your triggers will help. Another option is to get allergy shots, a long-term treatment that gradually makes you less sensitive to the things that set off your symptoms.
  • Steroids. In some cases, your doctor may prescribe inhaled steroids to bring down the swelling in the sinus membranes. For tough cases of chronic sinusitis, you may need to take steroids by mouth.

Sinusitis home remedies

While medicines can help, many cases of sinusitis go away on their own without any medical treatment. If you often get the condition, many of these same approaches will help you prevent it, too.

Humidity. Use a humidifier in rooms where you spend a lot of time. Follow the instructions for regular cleaning.

Breathe in steam vapors. You can either run the shower and sit in the bathroom, or breathe in steam from a bowl of warm (but not too hot) water. The steam vapors ease congested and swollen nasal passages.

Use warm heat. Put a warm, wet towel on your face. It can take off some of the pressure.

Sinusitis nasal washing. Also known as nasal irrigation, this is an at-home treatment that will flush out your sinuses and temporarily relieve your symptoms. One common type that you may have heard of is a neti pot. It’s a simple remedy but does need to be done with care. Here’s how it works. You squeeze or pour a saline solution -- you can buy one at your local pharmacy -- into your nostrils. That solution will thin your mucus and allow it to drain.

Nasal irrigation is not safe for everyone. Don’t use this remedy if:

  • You have an ear infection.
  • You have pressure in either or both of your ears.
  • You have a nostril that’s entirely blocked.
  • You have undergone surgery on either your ears or your sinuses.

You can make a homemade saline solution from a mixture of salt and water. But do not use tap water. It can contain tiny amounts of germs, pesticides, and other unwelcome substances that are safe to drink but don’t belong in your nose. They can cause serious, even fatal, infections. Here’s what to use instead:

  • Distilled water
  • Water labeled "sterile"
  • Water that’s been boiled for 3 to 5 minutes then allowed to cool until lukewarm and used within 24 hours (if stored covered)
  • Filtered water (only if using a filter labeled NSF 53 or NSF 58)

Drink lots of fluids. They'll help thin the mucus, which reduces the blockage in your sinuses. Cut down on alcohol, which makes the swelling worse.

Rest. When you've got a sinus infection, take it easier than normal. Get plenty of sleep, and give your body a chance to recover.

Sinusitis surgery

If over-the-counter and prescription medications don’t ease your chronic sinusitis symptoms, you might need sinus surgery. There are a few different procedures, and each aims to fix whatever is preventing your mucus from draining normally, whether that’s correcting a structural abnormality such as a deviated septum and removing benign growths, called polyps, or fungal infections. The different sinus surgeries include:

Endoscopic sinus surgery. In this procedure, your doctor will insert a thin tube with a camera and light at one end into your nose. This device, called an endoscope, allows the doctor to see precisely where to operate. The surgeon then uses tiny instruments to remove the problem -- shaving off tissue or bone, plucking out the fungal infection, or removing polyps.

Septoplasty. Surgeons perform this procedure to correct a deviated septum. This involves reshaping -- and possibly removing -- some of the bone or cartilage inside your nose. This can be done during endoscopic sinus surgery.

Balloon sinuplasty. Your doctor inserts a thin and flexible tube called a catheter into your nose and threads it to the blockage in your sinuses. Once there, the surgeon inflates a tiny balloon at the end of the catheter, then deflates and re-inflates it. This opens your sinuses, allowing them to drain and improving airflow.

Chronic sinusitis treatment

There are some other things you can do yourself to help with chronic sinusitis:

  • Warm compresses can ease pain in the nose and sinuses.
  • Drink plenty of fluids to keep mucus thin.
  • Saline nose drops are safe to use at home.
  • Over-the-counter decongestant drops or sprays can help. Don’t take them longer than recommended.

You also need to avoid any triggers linked to your sinusitis. 

If you have allergies, your doctor may recommend an antihistamine.

If a fungus is to blame, you’ll get a prescription for an antifungal medicine.

If you have certain immune deficiencies, your doctor may give you immunoglobulin, which helps fight the things your body reacts to.

If your symptoms do not get better, talk with your doctor. They might order tests to figure out why you still have symptoms. These can include:

  • A CT scan or other imaging tests. Imaging tests create pictures of the inside of the body.
  • A test to look inside the sinuses. For this test, a doctor puts a thin tube with a camera on the end into the nose and up into the sinuses.

There is no sure-fire way to prevent sinusitis. But there are some things that might help.

  • Don’t smoke, and avoid other people's smoke.
  • Wash your hands often, especially during cold and flu season, and try not to touch your face.
  • Stay away from things you know you’re allergic to. Talk to your doctor to see if you need prescription medicines, allergy shots, or other forms of immunotherapy.

If your sinus problems keep coming back, ask your doctor about the pros and cons of surgery to clean and drain the sinuses.

You’ll have pain and discomfort until it starts to clear up. In rare cases, untreated sinusitis can lead to meningitis, a brain abscess, or an infection of the bone. Talk to your doctor about your concerns.

Most of the time, sinusitis will clear up on its own. The symptoms can make you miserable, but they can be managed by easily available, over-the-counter medications. But if your symptoms don’t clear up or they go away and come back repeatedly, talk to your doctor about treatment.