Fall Allergies
Causes, Symptoms, and Testing 

School is starting back up, leaves are changing color, and there’s a crispness to the air. As spring and summer pollens fade away, the insects buzz off and the cooler weather moves in. You may be thinking you’re in the clear when it comes to allergy season, but that might not be the case.

What Causes Fall Allergies?

Autumn is prime time for a major allergen—weed pollen. Specifically, ragweed is the most common allergy trigger in the fall with pollen levels highest in early to mid-September.1 Other weeds that may prompt a fall sneeze are burning bush, cocklebur, lamb’s quarters, pigweed, sagebrush, mugwort, tumbleweed, and Russian thistle.1

To develop an allergy to allergens like these, you must first be exposed to them.2,3 If an allergy develops, your body will produce IgE antibodies as an immune response because it thinks the allergen is an invader, causing your allergy symptoms.2

Tree, Grass, & Weed Pollen

Along with ragweed, and depending on the region, elm tree, wall pellitory, goosefoot, Kentucky bluegrass, and Timothy grass may also pollinate into the fall months. Note that the types of trees, grasses, and weeds that bloom and cause symptoms may vary by region.


Mold, also called mildew, can be found outside on plants and in water, as well as indoors in places like the bathroom and kitchen. A wet, rainy spring can promote rapid plant growth that can extend past summer. This could lead to an increase in mold, causing symptoms that may last well into the fall.


Ragweed is the most common culprit for fall allergies.

It is a plant found in many regions that releases tiny pollen grains into the air during its blooming season, typically from August to November.1 Each plant lives only one season. But that one plant can produce up to 1 billion pollen grains!4 These pollen grains are lightweight and can travel long distances, making them easy to inhale. Ragweed pollen levels are generally highest in the morning hours when the air is cooler and calmer but can also stick around throughout the day.

Fall Allergy Symptoms

While summer transforms into fall, you may find that your sneezes and sniffles are lingering. Fall allergy symptoms, like other seasonal allergy symptoms, can range from mild to severe and occur outside or indoors.

Common fall allergy signs and symptoms include:

Runny nose Wheezing
Watery eyes Headaches
Sneezing Itchy eyes, nose, or throat
Coughing Dark circles under your eyes

Fall Allergy Testing and Management

Getting tested for fall allergies and effectively managing fall allergy symptoms go together like pumpkin and spice. To help find relief from allergy symptoms, you first must know what may be causing the reactions.

How Do You Get Tested for Fall Allergies?

In this season of change, it is time to learn more about what may be triggering your symptoms without waiting for an appointment with a specialist. One way to get tested for allergic sensitization is to speak to a healthcare provider about specific IgE blood testing. This test measures the amount of allergen-specific antibodies (IgE) in your blood. Depending on the levels of different antibodies, a healthcare provider can help you understand the potential cause of symptoms.

doctor talking to patient
mother and daughter gardening

Tips to Help Manage Fall Allergies

Work together with your healthcare provider to devise strategies to avoid your fall allergy triggers:1

  1. Monitor pollen counts, as mornings in the fall tend to have higher ragweed pollen levels.
  2. Keep windows and doors shut at home and in your car during high pollen days.
  3. Change your clothes after you’ve been working or playing outdoors.
  4. Wear a NIOSH-rated 95 filter mask when lawn mowing or working outside.
For more in-depth exposure reduction tips for each type of allergy, check out these Allergen Fact Sheets.
mother and daughter gardening

Fall Allergies Can Be Managed

Antihistamines not working? They may not always be the best option if you haven’t confirmed what you’re allergic to.

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In fact, in one study, 65% of people with allergy symptoms who used antihistamines were not allergic, meaning they may be wasting money and time trying to find relief.6

Speak to your healthcare provider about getting specific IgE blood testing to gain clarity into what is causing your allergy symptoms in the fall and start your journey toward relief.

Resources for healthcare providers

Specific IgE testing for fall allergies

Healthcare providers, click below, to learn more about how specific IgE blood testing can help in diagnosing seasonal allergies.

Practice parameters and guidelines

View practice parameters and guidelines for allergic rhinitis you may see in patients during fall allergy season.

Girl with inhaler with father and hcp

Allergen Encyclopedia

Explore our allergen encyclopedia, an easily shareable, patient-friendly resource that includes information on which pollen might be causing seasonal allergies as well as how they may impact food allergies and influence patient management plans.

  1. https://acaai.org/allergies/allergic-conditions/seasonal-allergies/. Accessed March 2024.
  2. Yoo Y, Perzanowski MS. Allergic sensitization and the environment: latest update. Curr Allergy Asthma Rep. 2014 Oct;14(10):465.
  3. Cox L, Williams B, Sicherer S, Oppenheimer J, Sher L, Hamilton R, Golden D; American College of Allergy, Asthma and Immunology Test Task Force; American Academy of Allergy, Asthma and Immunology Specific IgE Test Task Force. Pearls and pitfalls of allergy diagnostic testing: report from the American College of Allergy, Asthma and Immunology/American Academy of Allergy, Asthma and Ihttps://aafa.org/allergies/types-of-allergies/pollen-allergy/ragweed-pollen/mmunology Specific IgE Test Task Force. Ann Allergy Asthma Immunol. 2008 Dec;101(6):580-92.
  4. https://aafa.org/allergies/types-of-allergies/pollen-allergy/ragweed-pollen/. Accessed April 2024.
  5. https://acaai.org/allergies/allergic-conditions/ragweed-allergy/. Accessed April 2024.
  6. Szeinbach SL, Williams B, Muntendam P, O'Connor RD. Identification of allergic disease among users of antihistamines. J Manag Care Pharm. 2004 May-Jun;10(3):234-8.