Seasonal sniffles, constant congestion, itchy eyes: If these symptoms sound familiar, you’re not alone. Millions of people experience reactions to both outdoor allergens like pollen and grass, as well as indoor triggers such as dust mites, pet dander, and mold. But knowing what’s behind your symptoms can be tricky. That’s where understanding your immune system’s response, especially the role of IgE antibodies, becomes essential to your wellbeing.
To help you navigate allergy season and beyond, we sat down with Labcorp’s Dr. Matthew McCulloch, MD, a board-certified allergist and immunologist. He answers common questions about identifying symptoms, managing exposure, and how allergy testing can help you and your healthcare provider create a more personalized plan for feeling your best.
What is the difference between seasonal allergies and year-round (i.e., perennial) allergies?
Seasonal allergies happen only during certain times of the year. These are usually caused by outdoor plants releasing pollen. Tree pollen shows up in early spring, grass pollen in late spring and summer, and weed pollen in late summer and fall. People often notice their symptoms return during the same months each year. In some climates where it’s warm year-round, these seasons can vary and blend together.
Perennial (year-round) allergies happen all the time because their triggers are always around us indoors. Common year-round triggers include dust mites in bedding and carpets, pet dander from cats and dogs, mold in damp places, and small particles from insects like cockroaches.
If your symptoms show up mostly outdoors or during certain months, they are more likely seasonal. If they happen every week or year-round—especially indoors—they may be caused by indoor triggers. Knowing this helps guide the right testing and treatment.
What are the most common signs and symptoms of seasonal allergies?
Seasonal allergies tend to affect your eyes, nose, and sinuses. Common symptoms include:
- Sneezing
- Stuffy or runny nose
- Itchy, watery, or red eyes
- Itchy nose
- Post nasal drip (feeling mucus or drainage in the back of your throat)
- Feeling tired, especially if allergies interrupt sleep
- Cough
These symptoms happen because your body reacts to pollen as if it were something harmful. It releases chemicals that cause swelling and irritation in your nose and eyes.
Symptoms can often be worse on dry, windy days that stir up pollen or after spending time outside.
Sometimes, untreated allergies can impact your sinuses and ears as well.
How can you tell the difference between a cold and reactions to allergens?
Colds and allergies have a lot of similar symptoms, but there are a few things that can help you tell one from the other.
Both allergies and colds commonly cause a runny nose, sneezing, stuffiness, and coughing. If you’re experiencing fever or body aches, it’s most likely a cold since these are not common allergy symptoms. “Another clue is how long symptoms last,” says Dr. McCulloch. “Cold symptoms usually last less than 10 days.”
Allergy testing can also help tell the difference. If you already know you’re allergic to certain things and your symptoms show up during the same time those allergens are in the air, that’s another strong clue that allergies, not a cold, are causing your problems.
What types of indoor allergens most often trigger allergy symptoms, and what should people look for in their home environment?
Many people don’t realize how much the air inside their home can affect their allergies. The most common indoor triggers include:
- Dust mites (tiny bugs that live in bedding, pillows, and carpets)
- Pet dander (flakes of skin and proteins in fur or saliva)
- Mold (which grows in damp places)
- Small particles from cockroach waste
These can cause symptoms all year long because they stay inside the home unless steps are taken to reduce them.
Indoor spaces can also pick up outdoor allergens, especially during certain seasons. Pollen from trees, grasses, and weeds can easily follow you indoors by sticking to your clothes, hair, and shoes. Pets that go outside can bring pollen into the house on their fur, even if they don’t shed much. Opening windows, especially on windy days, can also let pollen blow inside, where it settles on furniture, floors, and bedding. Once pollen is indoors, it can continue to trigger symptoms even when you’re not outside.
Signs that indoor allergens may be affecting you include waking up congested, symptoms that get worse at night, musty smells, visible mold, or feeling worse after cleaning or vacuuming.
“Indoor allergens are easy to overlook,” says Dr. McCulloch. “But once you understand where they come from, both inside and outside, you can take simple steps to reduce them and feel better.”
What/when are typical allergy seasons?
Allergy seasons can vary a lot depending on the climate where you live. For example, in climates with year-round warm weather, some plants survive all year long, but in places with colder winters, they’re not present at that time to cause symptoms.
In most places in the U.S., allergy seasons typically follow this pattern:
- Spring: Tree pollen
- Summer: Grass pollen
- Fall: Weed pollen (like ragweed)
- Warm/humid months: Outdoor mold
These can also overlap, and warm winters may cause pollen season to start earlier. Rainy weather can increase mold levels. Windy days often make symptoms worse because pollen spreads easily.
Keeping an eye on pollen forecasts can help you plan your day and manage symptoms more effectively.
“You can check local pollen levels on many free apps or weather websites to help plan outdoor activities,” suggests Dr. McCulloch.
What are IgE antibodies, and how do they play a role in allergic reactions?
IgE antibodies are proteins your body makes when it mistakes harmless substances for threats. In people with allergies, IgE reacts to harmless substances like pollen, dust, or pet dander.
When you breathe in or touch an allergen, your IgE reacts and tells your body to release chemicals that cause allergy symptoms such as itching, sneezing, and runny nose.
Allergy blood tests measure the amount of IgE your body makes toward specific allergens. “These tests help us figure out exactly what you’re reacting to,” says Dr. McCulloch. “That way we can create a treatment plan based on your personal triggers.”
What lifestyle changes or environmental controls can help minimize reactions to common allergens like dust, dander, and outdoor pollen?
“Making small changes at home and in your environment can have a big impact on allergy symptoms,” shares Dr. McCulloch.
For outdoor allergies:
- Check daily pollen counts
- Keep windows closed during high-pollen days and use air conditioning instead
- Regularly replace your AC unit air filter
- Shower and change clothes after being outside
- Rinse your nose with saline spray to wash out pollen
- For people with grass allergies, avoid being nearby during mowing
For indoor allergies:
- Wash bedding weekly in hot water
- Use dustproof covers on pillows and mattresses
- Keep indoor humidity between 30–50%. Higher levels encourage dust mites and mold
- Run a HEPA air purifier
- Vacuum with a HEPA-filter vacuum
- Keep pets out of the bedroom so their fur and dander don’t build up where you sleep
- Reduce clutter and soft items that collect dust
When should someone consider allergy testing, and what are the benefits of early identification of allergens, especially for people with persistent symptoms or multiple triggers?
Allergy testing can identify your exact indoor and outdoor triggers so you can take action to avoid them more effectively. It can also help your healthcare provider choose the best treatments for your allergies. You should consider allergy testing if:
- Symptoms last more than a few weeks
- You’re not sure what’s causing your flare-ups
- Over-the-counter medicine isn’t enough
- You have asthma that you can’t control
- You have several triggers and want a better understanding of what’s actually causing your symptoms
“When we know your specific triggers, we can help you plan ahead,” says Dr. McCulloch. For example, some people start treatment before pollen season begins, which can prevent symptoms from becoming severe.
Allergies can be frustrating, but understanding why your symptoms happen is the first step toward relief. With clear insights into your sensitivities, you and your healthcare provider can develop a personalized plan to manage symptoms, reduce flare-ups, and take back control of your health all year long.
