Is It Allergies or Something Else?

You’re sneezing and sniffling, and you feel crummy. Allergies may be your first thought, especially if you have a history of them. An allergy is when your immune system reacts to something harmless, like pollen or pet dander, as if it were a threat. Your body releases chemicals called histamines, which cause things like sneezing, a runny nose, and watery eyes. But allergies aren't the only condition that can create these symptoms.

Respiratory allergies and colds look and feel a lot alike. Both cause sneezing, a runny or stuffy nose, and tiredness. But unlike allergies, colds are caused by a virus, so you can spread them to other people. A cold probably won’t give you itchy eyes. But you may have aches, pains, or a fever, which don't happen with allergies. Colds last 3-10 days. Allergies, though, can last an entire season or longer.

As with a cold, a virus causes the flu. The symptoms are also similar -- a runny or stuffy nose, a sore throat, and coughing. But in general, you feel worse with the flu than when you have a cold. The flu comes on quickly, with chills, muscle aches, and tiredness. It can also cause a high fever that lasts for a few days or longer. You’ll rarely have these more serious symptoms with a cold, and never with allergies.

Either allergies or COVID-19 can cause you to lose your sense of smell and have a runny nose. Otherwise, there’s not much overlap. COVID-19 is caused by a virus and is more likely to feel like the flu, or like a cold with a fever and cough. With COVID-19, you might also have shortness of breath. This usually doesn’t happen with allergies, a cold, or the flu. Some people with COVID-19 have no symptoms at all.

Wondering whether you have allergies or a sinus infection? One clue is itchy eyes. A sinus infection rarely causes irritated, watery eyes. Another symptom to look out for is thick snot that’s yellow or green. That’s more likely a sign of a sinus infection than allergies. Fever, tooth pain, and bad breath are also sometimes symptoms of a sinus infection. You won’t have them with allergies.

The main symptom that allergies and bronchitis share is a cough. With bronchitis, you may cough a lot and spit up mucus that’s clear, white, yellow, or green. You could also feel tired and short of breath, and have a fever, chills, or an ache in your chest. Bronchitis happens when airways in your lungs called bronchial tubes get inflamed. It can start as a cold or the flu. You can also get it from smoking.

You’ll feel most symptoms of strep throat in your mouth and neck. They include:

• A sore throat
• Pain when you swallow
• Red, swollen tonsils

Sometimes, strep throat gives you a fever, rash, or body aches. It doesn't make you cough or sneeze, though. Both strep throat and allergies can sometimes cause a headache. But for the most part, these two conditions don't look alike. And strep throat is caused by bacteria, not an immune reaction.

Congestion and trouble breathing through your nose are signs of allergies. But they could also mean a deviated septum. This happens when the cartilage between your nostrils is off-center. The condition has other symptoms, like nosebleeds and facial pain, that don’t happen with respiratory allergies. Your doctor can examine you to see if you have a deviated septum. You may need surgery to fix it.

Allergies and asthma often go hand in hand. The same things that trigger your respiratory allergies, like pollen and dust, can make asthma flare up. And doctors use some of the same treatments, like allergy shots, to treat both conditions. Both asthma and allergies cause a cough. But with asthma, you may also have:

• Trouble breathing
• Tightness in your chest
• Wheezing

This condition causes lots of sneezing, and a stuffy or runny nose. It looks a lot like a respiratory allergy, but it’s not caused by an immune system reaction. It can be set off by:

• Air pollution or strong odors
• Some foods (especially spicy ones) or drinks
• Certain medicines
• Weather changes
• Other ongoing health problems

You probably won’t have itchy eyes or a sore throat the way you would with allergies.