Cottonwood Allergies: Symptoms, Treatment, Seasonality, and More

Written by Kaleigh Moore
Published: March 21, 2023
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A native to the United States, and various parts of Mexico and Canada, the cottonwood is a towering tree that provides excellent shade. It grows rapidly, with its triangular-shaped green leaves shifting to a breathtaking gold color in the fall. Because they have long, flat stems, they swish in the wind, and the result is nothing short of stunning.

However – despite their incomparable beauty – cottonwood trees release lightweight pollen that ruthlessly torments allergy sufferers, affecting the quality of their lives. Yes, the allergen is not life-threatening; you can take several measures to reduce your symptoms. But waiting for the allergy season triggers anxiety in most patients. And if you’re asthmatic, your condition might worsen when the pollen count is at its highest.

This article delves into everything you should know about cottonwood allergies. Read on to discover when you’re at risk, the symptoms to watch out for, how to diagnose the condition, and the remedies to consider.

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Cottonwood Season in the United States

Eastern cottonwood tree in a forest seen upwards against a blue sky

Cottonwood allergies can spike from February to June.


Like ash and other well-known tree allergens, cottonwoods pollinate in the spring. Typically, the females release cotton-like seeds into the air, while the males produce pollen that travels quickly. This usually happens between late February and May in most states, but it’s not fixed. Understanding the allergy season in the US helps you to know when the cottonwood pollen will likely hit you, depending on the beginning and end of the period in your region.

More often than not, individuals with cottonwood allergy don’t even realize it. That’s why it’s essential to note the tell-tale signs of the condition and take adequate preventative measures in advance or seek treatment as soon as possible.

Common Symptoms of Cottonwood Allergies 

If you have cottonwood allergies, you’ll experience one or a few of these symptoms:

  • Sneezing
  • Coughing
  • Itchy and watery eyes
  • Nasal congestion
  • Runny nose
  • Sore throat
  • Aggravated symptoms for asthmatics, i.e., increased wheezing and shortness of breath

Cottonwood Allergy Tests

Allergy Test

A skin test can help determine if you’re allergic to cottonwood.


Roughly 100 tree species cause allergies during the tree allergy season, with some of the main offenders being ash, beech, hickory, date palm, and cottonwood. This makes it tricky to determine whether the latter’s pollen is the real cause of your allergy symptoms. Thankfully, you can take different tests to find out. 

Skin Tests

Also known as scratch or puncture tests, skin tests help to identify people allergic to cottonwood trees. So, here’s what happens during this procedure, whose wait time is only 15-20 minutes. An allergist uses a needle to prick and insert the cottonwood pollen into your skin. Then, they closely monitor you to see how the latter reacts to the allergen. You have a cottonwood allergy if it swells, reddens, or itches.

Your allergist can also use adhesive patches with cottonwood pollen to determine whether the allergen affects you. The allergy detection method requires them to place and leave the medical devices on your skin, only reviewing them after 48, 72, and 96 hours to see if there’s a reaction. 

Blood Tests

Some people have severe allergic reactions to skin tests and can’t use them to diagnose cottonwood allergies. A blood test is your best option if you’re in that lot. To perform it, the allergist will draw some of your blood to measure IgE antibodies. Elevated IgE (>100kU/l) indicates you’re allergic to cottonwood pollen. 

Unlike skin tests, IgE blood tests don’t cause allergic reactions, so they’re safe, even for young children. Since they’re consistent, accurate, and reliable, they expedite the treatment process and help identify other hidden risks, including allergic reactions that cross-reactivity might set off.

Unfortunately, it’ll take your allergist 1-2 weeks to deliver your blood test results. This laboratory analysis can also cause discomfort due to the needle test. And although it doesn’t present any serious risks, your arm will be sore for a day or two.

Skin Tests vs. Blood Tests: Which Is Better? 

Choosing between skin testing and blood testing remains an insoluble dilemma for most patients. But the truth is, your best bet boils down to your preferences and whether a particular method suits you.

For instance, a skin test could produce inaccurate results if you have hives, making a blood test more convenient. Again, blood testing is only suitable for patients who don’t mind needles. If you’re not a huge fan of them, choose adhesive patches to determine whether you have a cottonwood allergy. Either way, your allergist will explain the pros and cons of your preferred method, so you know what to expect.

Reasons to Get a Cottonwood Allergy Test

As you know, cottonwood allergies are not fatal. So you might ask yourself, “Is getting tested worth the hassle?” Well, it is! It helps confirm the condition, allowing you to seek proper medication at your earliest convenience. Since the allergy is incurable, you can only manage it and steer clear of cottonwood pollen when the trees produce it. 

In addition, a cottonwood allergy test could protect you against life-threatening reactions. For example, asthma symptoms are way worse during tree allergy season. Knowing that you’re allergic allows you to take the necessary steps to avoid cottonwood pollen and, consequently, severe asthma attacks. 

Another reason to consider cottonwood allergy tests is it lets you in on what you might pass on to your children. Remember, allergies are hereditary. It’s best to understand what your loved ones may suffer from to provide the best care and keep them happy despite the symptoms.

Tips to Prepare for a Cottonwood Allergy Test

Doctor holding a glass of clear fresh water, Doctor recommend drinking healthy water.

Hydrate well before your cottonwood allergy test.


When testing for cottonwood allergies, you want the most accurate results. That’s why you should prepare adequately to ensure nothing alters the latter. Wondering how you can do that? Here are some pointers:

Avoid Antihistamines

Steer clear of antihistamines 5-7 days before you take a cottonwood allergy test, including drugs with the compound. These medications make your skin less sensitive and can easily lead to a false negative or positive. 

If you’re considering a blood test, avoid taking other drugs before the procedure, as they might interfere with the results. Regrettably, this isn’t an option for patients with chronic conditions like heart disease. It’s best to consult an allergist to guide you on taking your medication and the allergy test simultaneously.

Don’t Apply Lotions

Lotions and other skincare products are also a big no-no when testing for cottonwood allergies. Remember, getting accurate results rides on the reaction between the antigens and your skin’s inflammatory cells. And applying ointments jeopardizes that.

Avoid Sun Exposure

10-30 minutes of sun exposure is good—it provides much-needed vitamin D, improves your mood, and boosts your immune system. But when you have an appointment with your allergist, avoid sitting too long in the sun to prevent sunburn that causes discomfort during allergy testing.

Wear Loose-Fitting Clothes

Cottonwood allergy tests involve skin pricks and require exposing your upper arm. Thus, wear comfortable, loose clothing when going to the hospital to provide easy access to the area. And avoid restrictive pieces such as arm sleeves because they irritate your skin, which is the last thing you want before the testing.

Eat and Hydrate

Enjoy a full meal before your cottonwood allergy test; an empty stomach is a distraction you don’t need. Also, drink a lot of water to ensure you’re hydrated, and carry some to your appointment. That way,  your veins will be plumper, making it easier for the allergist to draw blood if you prefer a blood test.

Here are a few things to refrain from taking up to two days before a cottonwood allergy blood test because they can affect the test results:

  • Alcohol
  • Soft drinks like Mountain Dew, Coke, 7UP, and Pepsi
  • Chocolate
  • Caffeine beverages, including coffee and espresso
  • Pre-workout supplements


Typically, most cottonwood allergy tests take 20-40 minutes, depending on the testing method. Growing anxious is easy as you await your allergist to complete the procedure. But don’t fret—it’s straightforward and isn’t painful, although you might experience some skin irritation.

If you feel unwell before your allergy test, postpone your appointment and call your allergist to reschedule.

How to Treat Cottonwood Allergies


Eye drops can help you manage your allergic reaction to cottonwood.


The best way to proceed after discovering you have a cottonwood allergy is to seek treatment to relieve the symptoms. Your top options should include the following.

Allergy Medications

Over-the-counter (OTC) allergy medications are effective remedies for cottonwood tree allergies. Examples include:

Nasal Sprays

Use a nasal spray if your allergy causes a stuffy or runny nose. It also reduces nasal swelling, inflammation, and sneezing. But remember to consult your doctor before making your pick since many types are available. Examples are intranasal antihistamines and intranasal steroids for patients with symptoms unrelated to cottonwood allergies. Here is one in particular that we like:

Nasal Spray for Allergies
Flonase Allergy Relief Nasal Spray
  • Non-drowsy allergy relief nasal spray
  • Provides relief from runny nose, sneezing and itchy eyes
  • Works for indoor and outdoor allergies
  • Easy to use
  • Eligible for HSA and FSA healthcare programs
Check Amazon


Most people use these drugs to treat cottonwood allergies because they relieve wheezing, nasal congestion, sneezing, coughing, and shortness of breath. Even so, they have undesirable side effects, which include but aren’t limited to:

  • Dizziness
  • Dry mouth
  • Rapid heart rate
  • Low blood pressure
  • Sore throat
  • Blurred vision
  • Muscle ache

If you do decide you wish to use an antihistamine, here’s one we like:

Proven relief from a proven company
Zyrtec 24 Hour Allergy Relief Tablets
  • Dependable relief from the trustworthy Zyrtec brand.
  • 24-hour formula.
  • Provides relief for the symptoms of Timothy grass.
  • Starts working within an hour.
Check Chewy

Eye Drops

Since cottonwood allergies cause watery and itchy eyes, these liquid drops can help to manage the symptoms. Opt for preservative-free options if you have sensitive eyes, and explore several reputable brands to discover those that work best for you.

One drop for relief all day
Pataday Once Daily Relief Allergy Eye Drops
  • One drop per day alleviates symptoms.
  • Easy to use.
  • Relieves itchy eyes.
  • Provides quick relief.
Check Chewy

Allergy Shots

Also known as immunotherapy, allergy shots provide a long-term solution to your cottonwood allergy problem. This procedure entails injecting a small amount of the tree’s pollen into your body and gradually increasing the dose until your immune system stops reacting to the allergen.

Allergy shot treatments are ideal for adults and children aged five years and above. Younger ones are barely cooperative and may not speak up if they experience the injections’ side effects. Moreover, an allergist should administer them weekly for 7-12 months and every 3-6 weeks afterward.

Immunotherapy doesn’t come with a specific protocol, so you can stop the shots whenever you see fit. But note that it takes up to five years to enjoy long-term relief. If there’s no improvement after the first year, your doctor could inject such a small amount of the cottonwood pollen that it’s insignificant. Missing multiple injections also limits the effectiveness of allergy shots.

Before embarking on your immunotherapy journey, beware of its side effects, including:

  • Hives
  • Rashes
  • Swelling and redness around the injected part of the skin
  • Watery eyes
  • Sneezing

Sublingual Immunotherapy (SLIT)

Allergy drops also treat allergic rhinitis, usually triggered by pollen from grass, weeds, and trees like cottonwoods. Although it’s a form of immunotherapy, it doesn’t involve injections—instead, you’ll place three drops of cottonwood pollen solution under your tongue for 1-3 minutes and then swallow them. Repeat this procedure daily or three days weekly for 3-5 years until your immune system grows impervious to the allergen.

SLIT comes with mild side effects for both adults and children, such as:

  • Redness of the eyes
  • Itching in the mouth and on the lips 
  • Diarrhea, abdominal cramping, and nausea
  • Hives
  • Nasal congestion and sneezing
  • Severe asthma symptoms

Allergy drops are legal, safe, and effective, even for pregnant women. But here’s a real bummer—as of this writing, the Food and Drug Administration (FDA) is yet to approve them for cottonwood allergy treatment.

ExACT Immunoplasty

As another form of immunotherapy, this innovative allergy treatment method introduces tiny doses of cottonwood pollen into your system through the inguinal lymph node. It’s fast and easy because it only takes 5-10 minutes and offers three ultrasound-guided procedures, four weeks apart. 

Here’s more to know about ExACT Immunoplasty:

  • It’s ideal for grown-ups and kids aged at least 5 years 
  • Your doctor must observe you for an hour after administering the allergen solution to know your body’s reaction
  • You shouldn’t take Beta blockers up to 24 hours before each treatment
  • One treatment series can include cottonwood pollen and two other allergens

Ways to Prevent Allergic Reactions to Cottonwood Pollen

Although you can’t cure cottonwood allergies, you can control their symptoms and avoid reacting to the tree’s pollen by minimizing exposure. Consider these tricks to do that when spring arrives.

Limit Your Outdoor Hours

Cottonwood pollen usually peaks in the morning and afternoon. Stay away from the allergen by only going out during the evening hours. And remember to wash off as soon as you go back indoors to keep it at arm’s length despite interacting with it outside.

Close Your Windows

Cottonwood pollen is dry and lightweight, allowing it to travel many miles away. Therefore, you’ll want to close your windows to keep it out of your home in spring, even if you don’t have a tree in your yard or vicinity.

Clean Your Home

Ensure your house is sparkling clean during the cottonwood allergy season to prevent the pollen from settling in your space. Use a HEPA-filter vacuum cleaner to trap the allergen, and do your laundry 1-5 times weekly to remove the particles from your bedding and clothes since they can easily stick to them.

Wipe Your Furry Pal’s Paws and Fur

The chances of your pet bringing in cottonwood pollen from the outdoors are high during the tree allergy season. Therefore, use a damp towel to wipe their coats and fur when entering the house, eliminating lingering particles. 

Effectively Manage Your Cottonwood Allergies

With awareness and proper medical attention, cottonwood allergies should be the least of your problems. Since you know the tree pollen season starts in February, do everything you can to prevent severe allergic reactions, and you’ll be safe. 

For instance, stock your medicine cabinet with OTC products to reduce cottonwood allergy symptoms. Researching these seasonal conditions to know the dos and don’ts also goes a long way in helping you lead a normal, stress-free life. 

The photo featured at the top of this post is ©

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