Is It Sinusitis or Allergies?

Medically Reviewed by Brunilda Nazario, MD on February 15, 2023
5 min read

You've had a stuffy nose for what feels like ages. It's gone on for more than just a few days, so you know it's not a cold. But which is it: sinusitis or allergies?

They have similar symptoms, so it's easy to confuse them. But there are key differences in the things that trigger them and the kind of treatment you get.

With both sinusitis and allergies, your nose and sinuses get stuffed up, but it happens for different reasons.

If you have allergies, the passages of your nose and sinuses swell because they're trying to flush out "allergens." That's just a technical word for anything you're allergic to, like pollen, mold, dust mites, and pet dander.

Sinusitis usually develops because of allergies or a cold. Sometimes, but not often, it's from bacteria that cause an infection.

When you have allergies or a cold, your nose and sinuses get inflamed. That blocks mucus from draining, which can cause an infection – not to mention pain and pressure.

If you have allergies, you're more likely to have sinus problems. That's because the inside of your nose and sinuses often swell up when you breathe in triggers.

There are eight sinus cavities in total: 

  • Two sinus cavities are in your forehead.
  • Two are behind each cheekbone.
  • Two sinus cavities are within the bones between your eyes.
  • Two are behind each eye.

They are paired, with one of each in the left and right side of the face.

Blockages. Each sinus has a narrow spot, called the transition space (ostium), which is an opening that’s responsible for drainage. If a bottleneck or blockage happens in the transition of any of your sinuses, mucus backs up.

An extra sinus. About 10% of people have one. It narrows that transition space.

Deviated nasal septum. Your nasal septum is the thin wall of bone and cartilage inside your nasal cavity that separates your two nasal passages. Ideally, it’s in the center of your nose, equally separating the two sides. But in many people, whether from genetics or an injury, it’s off to one side, or “deviated.” That makes one nasal passage smaller than another. A deviated septum is one reason some people have sinus issues. It can also cause snoring.

Narrow sinuses. Some people just have variations in their anatomy that create a longer, narrower path for the transition spaces to drain.

The symptoms of allergies and sinusitis overlap a lot. Both can give you a stuffy nose. If it's allergies, you may also have:

If it's sinusitis, besides a stuffy nose, you may have:

  • Thick, colored mucus
  • Painful, swollen feeling around your forehead, eyes, and cheeks
  • Headache or pain in your teeth
  • Post-nasal drip (mucus that moves from the back of your nose into your throat)
  • Bad breath
  • Cough and sore throat
  • Fatigue
  • Light fever

See your doctor to figure out what's going on, because it's tricky to know for sure.

If you have allergies, you'll start feeling symptoms soon after you come into contact with the stuff you're allergic to. Your symptoms keep up as long as you're still surrounded by those triggers.

Allergies can happen any time of year. They may be "seasonal," which means you get them only in the spring or fall. Or they may be year-round. For instance, you might be allergic to pets or mold, which can be a problem no matter the season.

Sinusitis usually happens after you've had a cold or allergies. But certain symptoms will keep going, even after your cold goes away. You'll probably have a stuffy nose and cough for more than a week or two.

You may hear your doctor talk about two kinds of sinusitis: "acute" and "chronic." There's a simple way to tell them apart. If your symptoms last less than 4 weeks, it's acute. If they go on for 3 months or longer, you have chronic sinusitis.

If you have allergies, the first thing you turn to may be decongestants or antihistamines. They're the most common treatments, and they ease a stuffy or runny nose, sneezing, and itching. Your doctor may also suggest corticosteroids, meds that reduce inflammation.

There is also a bioelectronic sinus device available that uses microcurrents on nerve fibers to help reduce sinus inflammation, pain, and congestion. 

If you have seasonal or year-round allergies, you may need a long-term solution. Your doctor might suggest you start your allergy medicine before the season begins. Or they may recommend allergy shots. For around 3 to 5 years, they'll give you regular injections of a small amount of whatever kicks off your allergic reaction. It's a bit like getting a vaccine. Your body develops an "immunity" and will have less and less of a reaction to your allergy trigger.

For sinusitis, antihistamines may help. You can also try nasal decongestant sprays, but you should use them for only 3-4 days. After that, you could get what's called the "rebound" effect. That means your symptoms start to get worse rather than better in between dosing and you feel the need to use more and more of the decongestant nasal spray. 

Another option are nasal sprays that have corticosteroids. You can use these as long as you need them. It may take several weeks before you get the full benefit.

You can also check out natural solutions for your symptoms. Try a humidifier, salt-water rinse, or hot pack.

If your sinusitis is caused by bacteria, your doctor may put you on a round of antibiotics. You may take them anywhere from 3-28 days.

Many doctors think antibiotics are overused. It's best not to take them unless your symptoms last longer than 7-10 days.

Use these tips to reduce inflammation and prevent problems:

  • Apply a warm, moist washcloth to your face several times a day to help open the transition spaces.
  • Drink plenty of fluids to thin the mucus.
  • Inhale steam two to four times per day. Sit in the bathroom with the hot shower running.
  • Use a nasal saline spray several times per day.
  • Wash your nose with a salt water solution from a neti pot.
  • Get a humidifier to moisten the air you breathe and help open sinuses.

If your sinus problems are related to allergies:

  • Avoid your allergy triggers.
  • Use antihistamines and decongestants if needed.
  • Talk to your doctor to see if you need prescription medicines, allergy shots, or other forms of "immunotherapy" (such as under-the-tongue tablets).
  • Lastly, if your sinus problems keep coming back, you can ask your doctor about the pros and cons of surgery to clean and drain the sinuses.

What would you like to learn about next?