Pollen Allergy

What is pollen allergy?

Pollen allergy is an allergy to pollen, the tiny particles released by trees, grasses and weeds. Pollen grains float through the air in spring, summer and fall – or year-round in areas with mild winters. On their way to fertilize plants and tree flowers, pollen particles often end up in our noses, eyes, ears and mouths, and cause allergy symptoms.

When is tree pollen allergy season?

Trees are the first plants to begin their mating process (which, after all, is what pollen is all about), releasing their pollen in late winter and early spring. Common tree allergens include:

  • oak
  • maple
  • birch
  • cedar
  • juniper
  • ashe juniper
  • mountain cedar
  • eucalyptus

Mountain cedar is an early bloomer in the south – often causing allergies in December in Texas and Oklahoma. It releases so much pollen that it looks like smoke in the air.

The Ashe Juniper tree, also known as mountain cedar, is found in Central Texas, Oklahoma, Missouri, Arizona and New Mexico. Unlike most trees in the United States, the ashe juniper releases its pollen between December 15 and February 15. The phenomenon is nicknamed “southwest cedar fever” or “Texas cedar fever.”

Some trees, like birch, only release pollen for a couple of weeks each year; others, like eucalyptus, pollinate all year long.

See the What is Tree Pollen Allergy? article to learn more about diagnosis and treatment. It also includes a tree pollen season chart,and cross reactivity food chart.

When is weed pollen allergy season?

Pollen allergy season for weeds, especially the potent ragweed, occurs in late summer and fall. Common weeds which can cause seasonal allergies in the fall include:

  • ragweed
  • burning bush
  • cocklebur
  • lamb’s quarters
  • pigweed
  • sage brush
  • mugwort
  • Russian thistle
A woman with long brown hair stands in front of blooming purple flowers, holding a tissue to her nose with both hands, appearing to sneeze. She wears a light headband, and the background is filled with greenery.

When is grass pollen allergy season?

Trees are followed by grasses in late spring and summer. Grass allergy is normally worse when the grass is pollinating. For the northern regions of the United States, this is primarily in the spring and early summer (April to June). For southern regions of the country, some grasses may cause year-round allergies.

What are the points to know about pollen?

  • Pollen that causes allergy tends to be small, light and dry. It is easily spread by wind over long distances. The pollen that gets all over your car or lawn furniture is not as much of an allergy problem as the pollen too small to be seen.
  • Bright-colored flowers actually release less pollen into the air than their drab cousins. Instead they depend on insects to carry pollen from one blossom to another.
  • Airborne pollen counts are usually highest early in the day just after the dew dries and on into late morning.
  • There is often a burst of pollen into the air when wind comes up just before a rainstorm. During and after the rain, however, pollen becomes damp and heavy with moisture, keeping it still and on the ground.
A man stands in a field of yellow flowers, holding a tissue to his nose. He appears to be sneezing or experiencing hay fever. The field is lush, with trees lining the background under a clear blue sky.

What do I need to know about pollen allergies and food?

Pollen-food allergy syndrome is an allergic reaction you can have to certain fresh fruits, vegetables or nuts if you have an allergy to birch, ragweed or grass pollen. Pollen-food allergy syndrome is also called oral allergy syndrome.

What are the symptoms of pollen allergies?

Symptoms of pollen allergies may be:

How do I know if I’m allergic to pollen or if I have seasonal allergies?

The only way to know for sure if you have a pollen allergy is to see a board-certified allergist for testing. In skin testing, the allergist will apply a small amount of diluted allergen to your skin and wait 15 minutes to see of a raised, itchy, red bump appears. If it does, then you have an allergy to that particular pollen. Blood testing for allergies is also available.

A woman in a purple sweater holds medication and a prescription while standing in a pharmacy. A pharmacist in a white coat is working in the background, surrounded by shelves with various health products.

How do you treat pollen allergies?

Over-the-counter and prescription allergy medications, such as antihistamines, decongestants and anti-inflammatory nasal sprays, can help relieve symptoms.

Most people should start taking their allergy medication about 1-2 weeks before their pollen season begins. For example, if you know your pollen allergies are worse in early spring, start taking your anti-inflammatory nasal sprays two weeks before symptoms are at their worst.

  • Antihistamines do exactly as the name suggests: reduce histamine created by exposure to pollen grains. Most are available over the counter.
  • Nasal decongestants also do exactly as they suggest: reduce congestion in the nose. They are for short-term use only. They should not be used for more than 3-5 days or congestion might worsen.
  • Corticosteroid nasal sprays work by reducing inflammation in the nasal passages. They should be used regularly during allergy season, rather than just as needed.

When you know you’re going to be outside for an extended period of time and exposed to pollen, it may be helpful to pre-medicate first. Use an antihistamine or corticosteroid nasal spray two hours prior to going outside. For eye allergies, use eye drops as needed.

Talk with your doctor about other medication options if antihistamines, decongestants and nasal sprays are not effective. Biologics are available for certain allergic conditions such as allergic rhinitis, chronic rhinosinusitis with nasal polyps and severe asthma. These medications treat the source of symptoms rather than the symptoms themselves.

Allergy shots, also called allergen immunotherapy, can provide long-lasting relief for pollen allergy. Allergy shots involve injecting small amounts of allergens into the body, gradually increasing the dosage over time. The goal is to desensitize the immune system to those allergens. This can help reduce or even eliminate symptoms of allergic reactions.

Sublingual allergen immunotherapy is also available as an alternative to allergy shots. This involves taking pills that dissolve under the tongue. Sublingual allergen immunotherapy is available for grass and ragweed pollen allergies.

Ragweed allergy is an allergy to ragweed pollen. Learn more about this type of allergy, including related foods.

How do you avoid pollen allergy symptoms?

Managing pollen allergies is a multi-step process, and patients need to be actively involved in their care. Along with visiting your primary care doctor or allergist and taking medication as prescribed, it’s important to find ways to reduce your exposure to pollen.

  • Use over-the-counter sterile saline eye drops and/or nasal spray frequently to flush out pollen from your eyes and nasal passages.
  • During pollen season, close your windows and run the air conditioner at home and in your car.
  • If you’re allergic to tree pollen, then you should avoid wooded areas, especially in the early spring when tree pollens are most prevalent. If you’re allergic to grass pollen, avoid lawns or fields, especially in the late spring when grass pollen is at its height.
  • If you buy trees for your yard, look for species less likely to cause allergy symptoms, such as crape myrtle, dogwood, pear, plum or redbud. You might also consider female varieties of ash, maple, poplar or willow trees.
  • Pollen can come inside on you and your clothing. Change your clothes when you get in and keep pollen off your pillow by showering and washing your hair before going to bed.
  • Dry your laundry indoors rather than outside.
  • Check daily pollen counts, but realize they often represent collections made 24-48 hours earlier. In addition, the amount of pollen it takes to set off symptoms varies considerably from one person to the next.
  • Check your area’s pollen forecast so that you’re aware of what’s coming in the days ahead. Many weather websites, including Pollen.com and the National Allergy Bureau, offer pollen forecasts.
  • Some people with severe pollen allergies may choose to wear a face mask designed to filter pollen and keep it from reaching nasal passages. If eye allergies are a problem, consider wearing sunglasses.

Are there certain times of the day that tend to be worse for allergies?

Airborne pollen tends to be highest early in the day, just after the dew dries, and on into early afternoon. High pollen levels can sometimes last until late afternoon. They can be most potent when conditions are warm, dry and breezy, and after a thunderstorm or rainfall.

The pollen count is never zero, so try to time your outdoor activities to when allergens are at their lowest. If you must be outdoors during high pollen times, avoid intense physical activity that causes rapid breathing. The faster you breathe, the more allergens you inhale. Exercise indoors, if possible.

Pine tree branches with clusters of reddish-brown cones release clouds of pollen into the air, set against a dark background.

Do allergy seasons really vary in intensity from year to year?

Many doctors and scientists say allergy seasons are intensifying, starting earlier and lasting longer. Climate change is a factor. It’s fueled in part by rising temperatures and mild winters, allowing pollen-producing trees and grass to bloom earlier. The extended growing seasons leads to increased levels of airborne allergens.

In addition, snowmelt in late winter or early spring can increase moisture that allows trees to produce more pollen when they bloom.

How do pollen allergies affect people with asthma?

People with asthma who have a pollen allergy to grass, tree or ragweed should be extra cautious as exposure can trigger asthma attacks.

It is important to keep your asthma well controlled by taking daily medications exactly as prescribed, avoiding triggers, and following your Asthma Action Plan. Know how to use your inhaler correctly so that you maximize the amount of medication that makes it to your lungs and airways. Review the instructions periodically and demonstrate your inhaler technique at every doctor appointment to confirm you’re using it correctly.

In the fall, ragweed pollen is believed to be one of the primary reasons for the September Asthma Peak – a time in mid-September when asthma-related hospitalizations and ER visits tend to spike, mostly among children. It happens soon after children go back to school and are exposed to more allergens as well as respiratory illnesses.

If you have allergic asthma, check your area’s pollen forecast daily so that you’re aware of what’s coming in the days ahead.

Questions & Answers (Q&A) on Pollen Allergies

You may have specific questions about how to treat pollen allergy symptoms. Here’s a Q&A with some common questions about this condition. If there’s a topic you’d like to see answered in this Q&A, please email the editor.

Yes, pollen can cause allergic rhinitis, which is also known as seasonal allergic rhinitis or hay fever. Pollen is one of the most common allergens that can trigger seasonal allergies. When pollen is inhaled by a person with allergic rhinitis, their immune system mistakes the pollen as a harmful substance and produces an immune response to fight it off. This immune response causes the classic allergy symptoms of sneezing, runny nose, itchy eyes and congestion.

If you suspect you have allergic rhinitis due to pollen allergy, speak with your healthcare provider to develop a treatment plan.

Yes, pollen allergy is closely related to hay fever, which is also known as allergic rhinitis. Pollen is one of the most common triggers of hay fever symptoms, which include stuffy nose, runny nose, sneezing, itchy nose and throat, and watery eyes.

Why is allergic rhinitis called hay fever? Hay fever often coincides with the time of year when hay is harvested and farmers are exposed to large amounts of pollen in the air. However, the symptoms can also be triggered by other types of pollen from trees, grasses, and weeds, and can occur at different times of the year depending on the pollen season.

Hey fever treatment starts with avoiding triggers. Stay indoors during high pollen counts and keep windows and doors closed. Remove your clothes and take a shower after being outside as pollen can sometimes attach to your clothing or hair. Use air conditioning to filter out pollen from indoor air. Keep your home free of dust and use a vacuum cleaner with a high-efficiency particulate air filter (HEPA filter).

When outside, you may want to wear a face mask to keep pollen from reaching nasal passages. You can also wear sunglasses to prevent eye allergy symptoms.

Many people treat hay fever with medications. Antihistamines are usually the first course of treatment. These over-the-counter medications can help reduce sneezing, itching, and a runny nose. Corticosteroid nasal sprays are prescription medications that can help reduce inflammation in the nasal passages.

Yes, there are natural ways to treat pollen allergies – but they may not work for everyone.

  • Nasal irrigation using a saline solution or neti pot can help remove pollen from the nasal passages and relieve congestion.
  • Vitamin C-rich foods, such as citrus fruits, broccoli, and strawberries, can help reduce inflammation and boost the immune system.
  • Quercetin is a natural antihistamine found in certain foods such as onions, apples, and berries. Supplements are available as well.
  • Probiotics from fermented foods such as yogurt or as a supplement can help improve gut health and boost the immune system, which can reduce allergy symptoms.

Does eating local honey help prevent or treat seasonal allergies? Allergists say this is a myth. The pollen collected by honeybees is far different from the pollen that causes seasonal allergies. Local honey has no impact on allergies.

Yes, corticosteroid nasal sprays can help reduce pollen allergy symptoms. Corticosteroid nasal sprays work by reducing inflammation in the nasal passages. This can help reduce pollen allergy symptoms such as sneezing, runny nose, and nasal congestion.

Corticosteroid nasal sprays can take several days to become fully effective, so it may be best to start using them 1-2 weeks before your pollen season begins. They should be used regularly during allergy season, rather than just as needed.

Dust masks can provide some protection against pollen and keep it from reaching your nasal passages. They filter out large particles in the air, such as dust and dirt. However, pollen particles are much smaller and can easily pass through the filter of a typical dust mask.

Instead of a dust mask, you may want to consider using a specialized allergy mask or a respirator with a filter designed specifically for filtering out pollen particles. These masks are typically labeled as N95 or N99 respirators and can be found at many hardware stores, pharmacies and online retailers.

You can find pollen count information online and many on TV news networks address it during pollen season. Online resources include:

Using these reports can help you plan our day.

Air conditioning can help to reduce indoor pollen levels that come into the house from open windows or clothes. Many air conditioning systems have filters that can trap pollen and other allergens. These filters can be effective at removing pollen from indoor air, especially if they are changed regularly. The most effective type is a high-efficiency particular air filter (HEPA filter).

Air conditioning should be one part of an overall strategy to avoid pollen or pollen allergies. Speak with your healthcare provider about other steps you can take to manage your symptoms.

The amount of pollen needed to trigger an allergic reaction varies. It can depend on your allergic sensitivity to a specific type of pollen, as well as the amount of pollen in the air. Some people may experience symptoms with even a small amount of pollen, while others may not be affected until the pollen count is much higher. Allergic reactions to pollen tend to be more severe when the pollen count is high and it is more likely to be inhaled.

Yes, allergy shots (also known as allergen immunotherapy) can be an effective way to prevent allergic reactions to pollen. They are available for grass and ragweed pollen. Allergy shots are typically recommended for people who have moderate to severe allergies, especially those who have not found relief with other treatments such as medications or avoiding allergens. They are commonly used to treat allergic rhinitis (hay fever) and allergic asthma.

Yes, hay fever (also called allergic rhinitis) is often triggered by pollen in the air. When people with a pollen allergy are exposed to pollen, their immune system overreacts and produces an antibody called immunoglobulin E (IgE). This triggers the release of histamine and other chemicals in the body, causing the symptoms of hay fever.

Yes, flowering plants produce pollen. Pollen is the male reproductive structure of flowering plants and is necessary for the fertilization of plants. When a flower blooms, it produced pollen that is then dispersed by wind, insects, or other animals. Pollen can travel to another flower, plant or weed, where new fertilization occurs. Pollen can also be inhaled by people, leading to allergy symptoms.

If you are experiencing allergy symptoms in late summer to early fall, you may have a ragweed allergy. These weed pollens are common from August through first frost in many parts of the United States. If you suspect you may have a ragweed allergy, talk with a healthcare provider. You may need to undergo allergy testing.

Reviewed by:
Don Bukstein, MD, FACAAI, is a board-certified allergist and immunologist and pediatric pulmonologist. He serves as Medical Director for Allergy & Asthma Network. Dr. Bukstein also volunteers at a Medicaid clinic in inner city Milwaukee. He is the former Director of Allergy and Asthma Research at Dean Medical Center in Madison, Wisconsin.