Woman sneezing and experiencing ragweed allergy symptoms

Ragweed allergy symptoms

Medically reviewed on August 1, 2022 by Karen Janson, M.D. To give you technically accurate, evidence-based information, content published on the Everlywell blog is reviewed by credentialed professionals with expertise in medical and bioscience fields.

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Seasonal allergies impact at least 60 million people in the US each year—nearly 20% of the population. [1,2]

A common seasonal allergen is ragweed, a plant that grows throughout the US. Ragweed season starts around late summer when pollen levels increase and continue until October. If you suffer from seasonal fall allergies, ragweed is one of many pollen-releasing plants that could cause allergic rhinitis (also called hay fever). But how is a ragweed allergy different from other seasonal reactions?

In this guide, we’ll explore everything you need to know about ragweed allergy symptoms, signs, causes, and treatment. We’ll also discuss potential prevention methods, including assessing your ragweed pollen allergy risk with at-home testing.

What is ragweed?

Common ragweed (Ambrosia artemisiifolia) is a native North American plant that grows throughout the continental US. [3] It’s widespread in Eastern and Midwestern States, where mild temperatures in the late summer and early fall encourage blooming and grass pollen dissemination.

Ragweed grows in areas where the land is likely to be disturbed, such as:

  • Tilled fields and farmland
  • Orchards
  • Manicured landscapes
  • Plant nurseries
  • Ditches, swales, and roadsides
  • Landfills and other waste dumping grounds

While each ragweed plant dies after just one season, a single plant can produce up to one billion pollen grains that can travel up to 400 miles away. [4]

Causes of ragweed allergy

Seventy-five percent of people who suffer from pollen allergies are specifically allergic to ragweed. The cause of ragweed allergy is similar to other seasonal, food, or environmental allergies—an incorrect immune response. [4]

Immune systems are designed to identify, fight, and eradicate foreign substances—such as bacteria, viruses, and toxins—when they enter the body. But when an allergic reaction occurs, the immune system incorrectly identifies a safe substance as a dangerous one, triggering immune responses.

In the case of pollen (which infiltrates the respiratory system), the immune system will initiate actions that flush pollen from the breathing passages and mucous membranes, like:

  • Coughing
  • Sneezing
  • Runny nose
  • Watery eyes
  • Itchy eyes

Scientists are still researching how people develop seasonal allergies, but current evidence suggests that allergies can be genetic or caused by environmental factors. [5]

Signs vs. symptoms

Signs and symptoms are two distinct markers used to diagnose a medical condition: [6]

  • Signs are distinct indicators of a particular disease. They’re verifiable via quantitative testing, and they’re typically identified by healthcare providers. For example, the presence of protein in your urine can be a sign of kidney disease.
  • Symptoms are subjective patient complaints. They can be helpful diagnostic tools, but they typically aren’t solely used to identify or confirm a condition. For example, urinating too much or too little is a symptom of kidney disease.

Signs of ragweed allergy

Since many symptoms of ragweed allergies overlap with more general seasonal allergy symptoms like mold allergy symptoms, healthcare providers rely on signs to specifically diagnose all allergies—including ragweed.

A sign of a ragweed allergy is a positive reaction in a controlled allergy test. Some allergy testing methods include: [7]

  • A Skin Prick Test (SPT)
  • An intradermal skin test
  • A physician-supervised, pill-based exposure test
  • Blood tests

The first three test types must be completed in a healthcare provider’s office (due to the risk of anaphylaxis after allergen exposure). Still, people who suspect they have seasonal allergies can complete indoor and outdoor allergy tests at home.

Symptoms of ragweed allergy

Ragweed allergy symptoms generally overlap with other seasonal allergy symptoms, including: [8]

  • Sneezing
  • Nasal congestion
  • Headaches
  • Irritated, itchy, or watery eyes
  • Scratchy or sore throat
  • Runny nose

There are two important additional considerations that people with ragweed allergies should explore:

  1. Asthma symptom aggravation – If you have (or develop) a ragweed allergy and already have a confirmed asthma diagnosis, pay attention to your symptoms. Ragweed and seasonal allergic reactions can exacerbate allergic asthma symptoms like coughing and wheezing.
  2. Oral allergy syndrome (OAS) – People with ragweed allergies may experience tingling, itching, or swelling in the mouth or throat when they eat certain raw fruits, vegetables, or nuts—a condition called oral allergy syndrome (OAS). OAS occurs when the immune system mistakenly identifies proteins in raw foods as ragweed pollen, inciting an allergic reaction.

Treatment and prevention for ragweed allergies

Healthcare providers typically recommend one of two treatments for ragweed allergies: [8]

  1. Allergy shots containing traces of pollen that can help your body build resistance
  2. Allergy medication like tablets that dissolve under your tongue

The following prevention methods could also reduce your risk of ragweed allergic reactions:

  • Avoiding pollen during the late summer and early fall by:
    • Keeping your doors and windows closed as often as possible
    • Staying indoors during the mornings, when ragweed pollen counts are highest
  • Changing clothes after spending time outside to prevent tracking pollen indoors
  • Taking a shower before bed to wash off any residual pollen
  • Testing for allergies and developing a proactive treatment plan with a provider

Conquer allergies and sensitivities with at-home testing

Ragweed allergy symptoms can range from a mild annoyance to a significant health risk (especially for people with asthma or oral allergy syndrome). Prevention is key—with the right tools, you can protect yourself from potential allergic reactions.

At Everlywell, we’re here to give you those tools. Our at-home allergy testing kit is simple, comprehensive, and convenient, and it can help you identify up to 40 common household and environmental allergens, like:

  • Pollen
  • Ragweed
  • Pet dander
  • Cockroaches
  • Grasses
  • Trees
  • Mold

Say goodbye to long lines at the lab. With Everlywell, you can take back the power of preventative testing.

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  1. US Centers for Disease Control and Prevention. Allergens. URL. Accessed August 1, 2022.
  2. US Department of Commerce. US Population Estimated at 332,403,650 on Jan. 1, 2022. URL. Accessed August 1, 2022.
  3. University of Florida IFAS Extension. Biology and Control of Common Ragweed Along Ditch and Canal Banks. URL. Accessed August 1, 2022.
  4. Asthma and Allergy Foundation of America. Ragweed Pollen Allergy. URL. Accessed August 1, 2022.
  5. National Library of Medicine. Risk Factors of Allergic Rhinitis: Genetic or Environmental?. URL. Accessed August 1, 2022.
  6. National Library of Medicine. Multiple Perspectives on Symptom Interpretation in Primary Care Research. URL. Accessed August 1, 2022.
  7. Asthma and Allergy Foundation of America. Allergy Diagnosis. URL. Accessed August 1, 2022.
  8. American College of Allergy, Asthma, and Immunology. Ragweed Allergy. URL. Accessed August 1, 2022.
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