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Weed Pollen Allergy

Weeds release tiny particles called pollen—some you can see, some you can’t. Because of their microscopic size, weed pollen easily travels in the air and can get in your eyes, nose or lungs. Everyone breathes in weed pollens, but not everyone has a reaction to it.

These symptoms are part of a reaction that is commonly called hay fever (even though weeds are not hay) - but is more appropriately called allergic rhinitis. If you have a weed pollen allergy and go outside on a day when it’s in the air, you’re likely to experience irritating symptoms like watery eyes or a runny nose.

Keep in mind that weed pollens, like grass and tree pollens, can travel far on windy days, so your reactions may not be because of the weeds in your yard or neighborhood. The source of your allergies could actually come from weeds miles away. 



Weed pollen allergy infographic

Click on your location to view a list of the allergens tested in your region:

Common Weed Pollens

There are hundreds of weeds that release pollen that can trigger your allergic reactions. Some of these weeds include:




Oilseed Rape


Rough Marsh Elder

Rough Pigweed

Russian Thistle

Sheep Sorrel


Common weed pollen allergy symptoms

Symptoms from a weed pollen allergy can be similar to those of many other seasonal allergies. Common weed pollen allergy symptoms can include:

  • Sneezing
  • Stuffy nose (nasal congestion)
  • Runny nose
  • Scratchy throat
  • Irritated eyes
  • Coughing
  • Wheezing
Asthma inhaler icon
Weed pollen can also increase asthmatic reactions in someone who is allergic.

Other cross-reactive symptoms

If you have a weed pollen allergy and have experienced an itchy mouth or throat after eating fresh fruit or raw vegetables, you may have Oral Allergy Syndrome (OAS). OAS is a cross-reaction that can occur when someone who is allergic to a weed pollen eats certain fresh fruits, vegetables, nuts or beans and has an allergic response. 

Learn more about OAS >

Examples of OAS:

If you're allergic to ragweed, you may feel itching or swelling in your mouth after eating bananas, cantaloupes, cucumbers, honeydew, watermelons or zucchini.

If you have an allergy to mugwort, you may react to bell peppers, broccoli, cabbage, cauliflower, garlic, onion, parsley or certain spices.2

Am I Allergic?

Am I Allergic?

You may be so used to dealing with your runny nose and irritated eyes that you might not consider asking for help. But how do you know if your symptoms are caused by a grass pollen allergy or not? Testing can help your healthcare professional determine what’s behind the endless sneezing and sniffles, so don’t try to manage the problem on your own.

A simple blood test—together with your medical history—can help identify underlying allergen triggers, if you have an allergy.A blood test can be done even when you are taking antihistamines.1 Knowing if you’re allergic and what you’re allergic to can help you, or a loved one, avoid or minimize symptoms.


Learn more about testing

Experience the comfort and convenience of an online diagnosis from a healthcare professional directly from your phone.


  1. Allergic Living. “Oral Allergy: Plants, Foods That Cross-React.” Allergic Living, 27 Mar. 2017, allergicliving.com/2010/08/30/the-cross-reactors/.
  2. Allergy blood testing: A practical guide for clinicians. Cleveland Clinic Journal of Medicine. 2011 September;78(9):585-592.