context: 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. The symptoms of allergies and sinusitis overlap a lot. Both can give you a stuffy nose. If it's allergies, you may also have: Runny nose and sneezing Watery or itchy eyes Wheezing 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. 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 he may recommend allergy shots. For around 3 to 5 years, he'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, which means your symptoms start to get worse rather than better. 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.