How Long Do Seasonal Allergies Last?

Seasonal allergies affect up to 30% of the global population, making allergy symptoms extremely common among adults and children. A seasonal allergy develops when your immune system overreacts to something in your environment, whether it’s burning bush in the fall or grass pollen in the spring. So how long do seasonal allergies last? It depends on the type of allergy you have and how you treat the symptoms.

In this article, you’ll learn about the most common seasonal allergy triggers, how long each allergy season lasts and what you can do to ease allergy symptoms at any time of year.

Allergies by Season

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Each season comes with its own set of allergy triggers based on the temperature, moisture level and other environmental conditions. One of the most common seasonal allergies is hay fever, also known as allergic rhinitis. Although hay fever is associated with spring allergens, the symptoms can last for several months. Other types of seasonal allergies can also span across several seasons. That’s why the answer to, “When is allergy season?” isn’t always so simple.

Spring Allergies

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Spring allergies typically begin in March and end in May. One of the most common allergy triggers for spring is pollen, the fine yellow powder found on plants. Insects and birds carry pollen from place to place, as does the wind. Pets also pick up pollen on their paws and carry it indoors, exposing you to higher levels of this allergen. At some points, the pollen count is so high that cars and trucks end up covered in the yellow powder if they’re parked outdoors for long periods of time. This is typically when the symptoms of a pollen allergy get worse.

If you’re allergic to pollen, you may experience the following symptoms:

  • Stuffy nose
  • Sneezing
  • Watery eyes
  • Runny nose
  • Wheezing
  • Itchy throat and/or eyes

Mold and Dust Mites

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Spring rain increases the amount of moisture in the air, creating the perfect environment for mold growth. Mold species — such as Penicillium, Aspergillus and Alternaria — trigger sneezing, itchy eyes, runny nose, cough and stuffy nose. If you have asthma, you may also start wheezing or experience shortness of breath. Mold has spores that travel through the air. When you breathe in, some of the spores may end up in your lungs and make your allergy symptoms worse.

Dust mites also thrive in high levels of humidity, making spring a common time for dust mite allergies to flare up. These mites don’t bite or sting, but they do feed on the dead skin cells your body sheds. Dust mite allergies aren’t usually caused by an allergy to the mites themselves, but by an allergy to proteins found in their waste products. Dead mites also produce these proteins as they break down. If you have a dust mite allergy, you may experience sneezing, watery eyes and a runny nose. For people with asthma, dust mites are a major trigger of asthma attacks.

Other Spring Allergens

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During the spring, plants flourish, causing them to grow rapidly. Trees grow new leaves, weeds pop up around the yard and grasses grow much taller and greener. As a result, you may experience worsening allergy symptoms. Birch trees, juniper trees, maple trees, Bermuda grass and fescue are all examples of plants that can trigger spring allergies.

Summer Allergies

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Summer allergies begin in June and end in September, but they typically peak in June and July. If your summer allergies seem especially severe, it may be because you naturally spend more time outdoors during this time of year. Swimming, hiking and attending cookouts can all put you into contact with more allergens than usual. You may develop allergy symptoms if you’re exposed to these common allergens:

  • Mold
  • Tree pollen
  • Nettle
  • Mugwort
  • Grass pollen
  • Ragweed

Fall Allergies

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Next to spring allergies, fall allergies are the most common, beginning in late summer and continuing through September or October. How long your fall allergy symptoms last depends on where you live. In cooler areas, fall allergy season typically ends in September. It may extend through October if you live in a milder climate. Ragweed travels long distances, so be aware that you could experience symptoms of a ragweed allergy even if you don’t have a lot of ragweed in your neighborhood. Mold and dust mites are also common allergens during the fall.

Winter Allergies

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During the winter, the pollen count drops, and you start spending more time indoors. That’s why many people are surprised to find out that their allergy symptoms continue from November through February. Even though you’re not exposed to as much pollen, you spend more time around dust mites, pet dander, mold and other indoor allergens. Turning on your furnace disturbs these allergens, increasing your exposure. Your symptoms may be even worse if you have central heating, as allergens can easily travel through the vents in your home.

Seasonal Allergy Symptoms

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Although each season comes with different allergy triggers, there’s a lot of overlap in the symptoms they cause. You may experience itchy eyes, runny nose, watery eyes, coughing, sneezing or dark circles under your eyes. If you’re allergic to dust mites, you may also have sinus pressure, red eyes or itching in your throat or on the roof of your mouth.

During the spring, pollen settles on fruits and vegetables, so you may consume it rather than breathing it in. If you do, you may have an itchy tongue or experience itching on the roof of your mouth. Some people with seasonal allergies also develop postnasal drip, which causes mucus to drip down the back of the throat.

Why Won’t Your Seasonal Allergies Go Away?

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If you react to multiple allergens, it may seem like your seasonal allergy symptoms never go away. The seasons also tend to overlap, so even if you only react to one or two allergens, you may be exposed to them for several months at a time. Allergy symptoms tend to persist if you don’t take steps to reduce your exposure to common allergens.

For severe allergies, it’s important to wash your hands regularly, stay indoors when the pollen count is high and keep windows closed to prevent allergens from entering your home. If you’re allergic to dust mites, washing your bedding regularly can reduce the number of mites in your bedroom. People with severe allergy symptoms may also need to take the following precautions:

  • Wear a mask when spending time outdoors.
  • Avoid pulling weeds, mowing the lawn and doing other activities that increase exposure to environmental allergens.
  • Wash clothing immediately after spending time outdoors.
  • Use an air purifier with a highly efficient filter to remove allergens from the air.

Manage Seasonal Allergy Triggers With Air Purification

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One of the best ways to ease seasonal allergy symptoms is to eliminate as many allergens as possible from your home. Air purification uses filters to remove tiny particles from the air, reducing your exposure to allergens, which makes it easier to breathe. Some filters trap pollen, dust mites and other extremely small molecules, while others break these molecules down into harmless substances.

To get the most out of your air purifier when combating allergies, put it in your bedroom to reduce the amount of pollen and other allergens you breathe in while sleeping. Consider taking the following steps to make your symptom management even more effective:

  • Keep pets out of the bedroom to prevent dander from getting trapped in your bedding.
  • Use high-efficiency filters in your HVAC system.
  • Replace carpeting, which traps allergens, with wood, laminate or other hard surfaces.
  • Use window blinds or shades instead of curtains.
  • Wash sheets and blankets frequently. Use hot water if possible.
  • Put a plastic cover over your mattress.

PECO Filter Technology to Destroy Allergens

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Photoelectrochemical oxidation (PECO) has revolutionized air purification by not only capturing allergy triggers and other pollutants, but also destroying them. Traditional purification just collects particles on a filter that eventually becomes a source of allergens. That’s where PECO filter technology comes in.

PECO filters are capable of destroying organic particles like mold and pollen to reduce allergens indoors. Pathogens like bacteria and viruses are also destroyed by PECO, which helps reduce the risk of exposure to the cold, flu, and other illnesses. 

How PECO Filtration Works

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PECO filtration works by producing free radicals inside the filter from water molecules present in the air. These free radicals act as oxidizers, triggering chemical reactions that break down microorganisms and organic matter into carbon dioxide, water and trace minerals. Allergy-causing particles destroyed in this way can’t return to the air, which makes it easier to manage your seasonal allergy symptoms.

Shop Molekule’s Air Purifiers for Seasonal Allergy Relief

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Take a stand against your seasonal allergies and visit Molekule to learn more about the science behind air purification and browse our selection of award-winning air purifiers.

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Molekule was founded on decades of research into improving air purification through invention and innovation. We value the scientific method and supporting facts with peer-reviewed research.