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.
Common ragweed (Ambrosia artemisiifolia) is a native North American plant that grows throughout the continental US.  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:
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. 
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. 
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:
Scientists are still researching how people develop seasonal allergies, but current evidence suggests that allergies can be genetic or caused by environmental factors. 
Signs and symptoms are two distinct markers used to diagnose a medical condition: 
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: 
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.
Ragweed allergy symptoms generally overlap with other seasonal allergy symptoms, including: 
There are two important additional considerations that people with ragweed allergies should explore:
Healthcare providers typically recommend one of two treatments for ragweed allergies: 
The following prevention methods could also reduce your risk of ragweed allergic reactions:
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:
Say goodbye to long lines at the lab. With Everlywell, you can take back the power of preventative testing.