What Is Ragweed Allergy?

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From late summer to early autumn, ragweed pollen is released from plants in areas throughout the United States, causing more than 23 million people across the country to suffer symptoms of ragweed allergy : sneezing, watery and itchy eyes, and runny nose.

For those with asthma, ragweed allergies, also known as hay fever, can trigger asthma attacks. Being prepared for ragweed season can help you avoid allergy symptoms and asthma triggers.

Ragweed Allergy Symptoms

Theresa Chiechi / Verywell

Ragweed Allergy Symptoms

Ragweed allergy—similar to other pollen allergies such as tree, flower, and grass—may cause a variety of symptoms. These appear in August and September and last until October or November, depending on the climate.

For people who are allergic to ragweed, contact with its pollen will stimulate an immune system reaction, causing common allergy symptoms including:

If you have allergic asthma, ragweed can trigger additional symptoms such as:

As you repeatedly fight the effects of ragweed during these months, you may also begin to suffer additional difficulties, including problems sleeping, which can result in chronic fatigue and loss of concentration. This can lead to poor performance at school or work.


Like most pollens that cause allergies, ragweed pollen spreads through the air. Pollen levels are highest during the morning hours, on windy days, and shortly after rainstorms when the plant is drying out.

Ragweed is harmless, but some people's bodies mistakenly identify it as a threat and launch an attack against it. That activates the immune system, which releases a substance called histamine. It's histamine that causes itching and swelling.

If you have allergic asthma on top of a ragweed allergy, the histamine release also causes bronchoconstriction and excess mucus, which can lead to breathing problems like coughing or wheezing.

Oral Allergy Syndrome

Oral allergy syndrome (OAS), or fruit-pollen syndrome, is considered a mild type of food allergy. Symptoms of OAS include itching and tingling in the mouth and throat after you eat certain fresh fruits or vegetables.

Ragweed allergy is sometimes related to this. Some may experience consistent OAS symptoms year-round, while others may notice that they get worse during ragweed season.

People with ragweed allergy and OAS are most often sensitive to:

  • Banana
  • Melon (cantaloupe, honeydew, watermelon)
  • Zucchini
  • Cucumber
  • Squash
  • Potato

Different allergies (e.g., grass, birch pollen) are associated with different food sensitivities.


If you have allergy symptoms in the late summer and early fall, pay attention to what appears to trigger them (such as where and when they tend to happen) and talk to your healthcare provider. They'll likely send you to an allergist who can perform a skin test to see whether you have a ragweed allergy.

During the test, the healthcare provider will prick, puncture, or scratch your skin and place a diluted ragweed sample on the surface. After 15 minutes, if you've had a reaction, it indicates you're allergic to this type of pollen. You may be checked for numerous other allergies in the same way.


While ragweed allergy can't be cured, you can manage the symptoms and decrease both the frequency and severity of allergy flare-ups. If you have asthma, proper allergy management can temper your immune response and help you avoid asthma attacks as well.


Because ragweed exists nearly everywhere and tends to occur in large amounts from August to October, total avoidance can be difficult.

However, you can check out the pollen counts provided by the National Allergy Bureau and take extra precautions to limit your exposure when ragweed levels are high in your area or it's especially windy. At those times:

  • Stay indoors as much as possible.
  • Keep windows closed to prevent outdoor pollen from drifting into your home.
  • Minimize early morning outdoor activity (from 5 a.m. to 10 a.m.), when the most pollen is usually emitted.
  • Keep car windows closed when driving.
  • Vacation in low-pollen or pollen-free areas (e.g., beachside, a cruise, cooler climates)
  • Don't hang laundry outside to dry.
  • Use a high-efficiency particulate air (HEPA) filter to remove some ragweed pollen from your home.
  • Shower and put on clean clothes after going outside.
  • Give a daily bath to pets that go outdoors.


If avoiding ragweed pollen doesn't sufficiently prevent your symptoms, you may consider medical treatments. Many of them are available over the counter, but you should talk to your healthcare provider about which are likely to be the safest and most effective for you. Prescription medications also are available.

Some daily treatments should be used starting two weeks before allergy season, whether you are feeling the effects of ragweed already or not. If you're not sure when to start a drug, ask your healthcare provider or pharmacist.

The treatment generally is the same as for other types of pollen allergies, including:

  • Nasal steroid sprays
  • Antihistamines
  • Allergen immunotherapy

Nasal Steroids

Medicated nasal steroid sprays are used once a day during ragweed season, whether or not you have symptoms. Considered more effective than antihistamine medications, sprays decrease nasal inflammation to help prevent sneezing, itchy nose, runny nose, and congestion.

Depending on what allergies you have, your healthcare provider may prescribe these for use during allergy season or year-round.

Common nasal steroids include:


Often called "allergy pills," some antihistamines are designed for daily use while others are taken to combat symptoms after they arise.

Common daily-use antihistamines include:

Some evidence suggests Clarinex and Xyzal may be most effective for ragweed allergies.

As-needed antihistamines include:

Leukotriene Receptor Antagonists

These drugs are used to treat allergy symptoms and prevent asthma symptoms, and some evidence shows them to be especially effective against ragweed allergies.

In asthma, leukotriene antagonists are prescribed as add-on medication when another controller medication doesn't control symptoms well enough. If you have ragweed allergies and need an add-on drug, you may want to ask about a drug in this class.

Some leukotriene receptor antagonists on the market are:

Allergen Immunotherapy

Also known as subcutaneous immunotherapy (SCIT) or, more simply, allergy shots, immunotherapy targets the underlying cause of allergies rather than treats the symptoms.

The treatment involves a series of injections just below the skin that contain small amounts of the substances you're allergic to so that, with time, your body stops producing allergic antibodies to it. The end goal is fewer, milder allergy symptoms.

You usually need to get the shots on a regular schedule for three to five years. This is a commitment, but the effects can last for up to a decade after the last injection.

In addition to preventing an allergic reaction to ragweed, SCIT is an effective way to help manage symptoms in people over 5 with allergic asthma who are sensitive to ragweed, according to recommendations issued by the National Institutes of Health in December 2020.

The guidelines specify that SCIT is appropriate for people whose asthma is not well-controlled but should not be given to anyone with severe asthma or who is experiencing asthma symptoms. If you have allergic asthma and a proven sensitivity to ragweed, ask your healthcare provider if allergy shots might be an option for you.

Saline Rinse

Some people with allergies benefit from performing a saline (salt water) rinse using a device like a Neti pot or squeeze bottle, as needed. This is an inexpensive and simple procedure that's believed to thin the mucus and remove allergens from your sinuses.

Some scientific evidence suggests that saline rinses can be effective in some people for up to three months after they're discontinued. However, a review of studies called it low-quality evidence.

A Word From Verywell

Managing seasonal allergies can sometimes feel like a no-win battle. While it's possible for many people to just live with the symptoms, others' day-to-day may be significantly affected by them. If you have allergic asthma, those inconvenient sniffles and itchy eyes are signs that something more serious may develop.

Work with your allergist to get ragweed reactions under control so you can feel your best.

14 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Pat Bass, MD
Dr. Bass is a board-certified internist, pediatrician, and a Fellow of the American Academy of Pediatrics and the American College of Physicians.