Think allergy season is over? Not so fast, says doctor

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The arrival of spring is traditionally associated with allergies, but the fresh air brought by fall’s cooler weather doesn’t necessarily mean everyone can breathe a little.

For many allergy sufferers, fall is peak season, likely made worse by global warming. Allergy season is starting earlier and lasting longer, which scientists attribute to a variety of causes, including the climate crisis.

As temperatures remain warmer and the first frosts are delayed, plants that release allergens have more time to grow. Additionally, higher levels of carbon dioxide in the atmosphere from fossil fuel use and emissions stimulate more plant growth, generating more pollen. More than one in four adults in the United States suffered from seasonal allergies in 2021, according to the U.S. Centers for Disease Control and Prevention.

It’s good to know common fall allergy triggers and the symptoms people can expect. Since respiratory viruses are also prevalent in cold weather, how can people distinguish between seasonal allergies and a virus? What can be done to diagnose specific triggers and how can people relieve their symptoms?

To help us answer these questions, I spoke with CNN wellness expert Dr. Leana Wen. Wen is an emergency physician and adjunct associate professor at George Washington University, and she previously served as Baltimore’s health commissioner.

CNN: What are common fall allergy triggers?

Dr. Leana Wen: The most common culprit is a plant called ragweed. Ragweed grows wild throughout the United States. A plant can release 1 billion pollen grains. Ragweed season typically begins in August and peaks in September, but can last into November.

Other plants that can trigger fall allergies include burning bush, gramwort, amaranth, mugwort, and tumbleweed. Mold can also cause seasonal allergies. In the fall, mold can accumulate in dead leaves and hay bales as well as indoors in damp areas.

CNN: What symptoms should people expect?

Magnifying glass: Common symptoms include a runny or stuffy nose, sniffling, sneezing, coughing, watery eyes, scratchy throat, and itching and burning in the nose, mouth, and eyes.

CNN: Since respiratory viruses are also prevalent in cold weather, how can people distinguish between seasonal allergies and a virus?

Magnifying glass: There is no simple answer. Allergies tend to follow a seasonal pattern and become worse during certain times of the year. Symptoms persist for at least a week, usually longer. Many people experience the same symptoms year after year. Some symptoms more correlated with allergies than with the common cold are itchy nose and throat and red, watery eyes.

Respiratory infections can also follow a seasonal pattern and are generally more common in winter than in spring and fall, which are the classic allergy season. A key distinguishing factor is the presence of fever. Seasonal allergies do not cause fever. They also tend not to cause body symptoms such as aches and fatigue. And although people with allergies can develop a cough, the presence of a cough should suggest respiratory infections.

People who have had allergies before often know what works to treat them. Relief from allergy medications is a good sign that the symptoms are due to allergies. People can also get tested for various viral infections. There is no laboratory test for many cold viruses, but there is for the flu, Covid-19, and RSV (respiratory syncytial virus). Some hospitalized patients may also receive a viral panel including a broader range of other respiratory viruses. The US government has just made a new series of at-home Covid-19 tests available free of charge.
It’s a good idea to sign up for free testing while we have the chance.

CNN: How to diagnose specific allergy triggers?

Magnifying glass: Some people want to know exactly what triggers their allergies. They should contact their primary care provider for referral to a specialist trained in allergology and immunology. This clinician may perform a skin test, where they place a small drop of different allergic triggers on your skin to see if there is a reaction. They may also recommend a blood test to look for antibodies to the allergen.

CNN: What do we need to know about allergy triggers that could cause problems all year round?

Magnifying glass: Spring and fall tend to be peak allergy season because that’s when a lot of pollen is released, but there are other triggers as well. It is worth mentioning dust mites, which are microscopic organisms that feed on household dust and humidity in the air. This is a common type of indoor allergen and can cause symptoms year-round.

I have a dust mite allergy and a very severe ragweed allergy. So even though I have allergy symptoms year-round, they get especially bad in the fall.

Another category I want to highlight is food allergies. Nearly 6% of adults and children have food allergies, according to the U.S. Centers for Disease Control and Prevention. These are different from seasonal allergies and can cause serious or even fatal reactions.

CNN: What treatments can help people relieve their symptoms?

Magnifying glass: There are a variety of treatments that can help control seasonal allergies. To begin, people should try to reduce their exposure to the allergen. If ragweed is the problem, limit time spent outdoors when pollen counts are high, which is usually from morning to early afternoon.

Change your clothes when you come indoors after outdoor activities. Keep windows and doors closed in the house and close car windows while driving. Dry laundry indoors rather than hanging them on a clothesline outside.

Medications may include antihistamine pills and nasal sprays to relieve congestion. There are many over-the-counter options, as well as some available only by prescription. People with severe symptoms may benefit from immunotherapy, also called an allergy shot.

It is always advisable to consult your doctor or other healthcare professional before starting any new drug treatment. Some people respond well to over-the-counter options, while others may need a prescription medication or a combination of therapies.

Keep in mind that just because a medication is available over the counter does not mean it has fewer side effects. Diphenhydramine, an antihistamine, is sedative and can be very dangerous when taken in large quantities. And many nasal decongestants have interactions with other medications and are not intended for long-term use.

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