As many as 80 million people in the United States live with allergies. While spring and summer allergies often get the most attention, symptoms frequently return or worsen during the fall season. For some, fall allergies feel like a lingering problem that lasts for weeks.

What Triggers Fall Allergies?

In most parts of the United States, weed pollen is the main cause of fall allergies. The biggest culprit is ragweed pollen, which grows wild across the Midwest and East Coast. Ragweed levels usually peak in mid-September, but the plant can release pollen from August through November.

Ragweed pollen spreads easily, especially on windy days. Checking the daily pollen count can help you plan outdoor activities and limit exposure when levels are high.

Pollen is not the only trigger during the fall allergy season. Other common allergens include:

• Mold spores, which thrive in damp piles of leaves, soil and decaying plants. Outdoor mold levels rise in the fall, and spores are often tracked indoors on shoes, clothing and pets.
• Dust mites, which can worsen symptoms as people spend more time indoors when temperatures drop.
• Pet dander, which can build up indoors when pets spend more time inside.
• Certain raw fruits and vegetables, which may trigger symptoms in some people with a condition called oral allergy syndrome (OAS). OAS is a type of food sensitivity that can occur in people with pollen allergies. It happens when the immune system reacts to proteins found in certain raw fruits and vegetables that resemble those found in tree, grass or weed pollen. Reactions are typically mild (itchy mouth or mild swelling) but should be discussed with your doctor if they worsen.

“When you're allergic to ragweed, your body makes antibodies to ragweed,” says Cheryl A. Steiman, MD, an allergist and immunologist at Northwestern Medicine. “Some fruits and vegetables can look like ragweed allergen to your immune system. This can cause a cross-reaction.”

Common Fall Allergy Symptoms

Although triggers change, allergy symptoms often stay the same from season to season. Fall allergy symptoms may include:

• Runny nose
• Sneezing
• Stuffy or congested nose
• Watery eyes
• Itchy eyes
• Postnasal drip
• Fatigue or trouble sleeping

“Allergies often feel like a long-lasting cold that returns around the same time each year. Clear, watery mucus is more typical of allergies,” says Dr. Steiman. “People also commonly associate them with an itchy nose and eyes and frequent sneezing.  Symptoms usually follow a seasonal pattern or recur with specific triggers.”

If symptoms come on suddenly with a fever or body aches, you may be dealing with an illness or another condition rather than allergies. If you're not sure, you can check with a healthcare professional.

How To Reduce Allergy Exposure at Home

While it is not always possible to avoid allergens completely, small steps can reduce exposure and ease symptoms. Helpful tips include:

• Keep windows closed on high-pollen days, especially in the morning.
• Shower and change clothes after spending time outdoors.
• Leave shoes at the door to avoid bringing pollen and mold inside.
• Wash bedding weekly in hot water to reduce dust mites.
• Use high‑quality HEPA filters in your home and change them regularly.
• Clean damp areas to prevent mold growth.
• Bathe pets often to reduce pet dander indoors.

These steps are especially important during peak fall allergy season.

Medications and Treatment Options

Many people feel better with over‑the‑counter medications available at pharmacies and grocery stores.

Common options include:

• Antihistamines to reduce sneezing and runny nose
• Nasal sprays, which can help with congestion and swelling
• Eye drops for itchy or watery eyes

Using medications correctly is important. Some nasal sprays work best when used daily, not just when symptoms are severe. Your doctor can help you choose the right option and avoid side effects.

If symptoms do not improve, prescription medications may be recommended.

When Allergy Testing Makes Sense

If symptoms continue despite treatment, an allergist can perform testing to identify specific triggers. Skin testing is a quick and common way to detect sensitivities to pollen, mold, dust mites and pet dander.

Once you know your triggers, you can follow a personalized plan to reduce exposure and better manage symptoms.

“Skin testing helps identify the exact triggers for allergic symptoms,” says Dr. Steiman. “It helps us find ways to avoid triggers. It also helps us choose the most effective treatment plan.”

Are Allergy Shots Right for You?

For people with ongoing symptoms, allergy shots (also called immunotherapy) may be an option. These injections help train the immune system to react less strongly to allergens over time.

Treatment usually begins with weekly shots, then moves to monthly injections for several years. While allergy shots require a long-term commitment, they can significantly reduce symptoms and decrease the need for daily medications.

When To Seek Medical Care

If allergies are starting to disrupt your daily routine, it may be time to see a doctor, especially if:

• Symptoms make it hard to sleep or get through the day.
• Over-the-counter medications are no longer helping.
• You have asthma and symptoms worsen during the fall.
• You're not sure what is causing your symptoms.

A primary care doctor is often a good place to start. They can help evaluate your symptoms and recommend next steps for treatment.

“An allergist can also help determine whether allergy shots are a recommended treatment approach,” says Dr. Steiman.

Take Charge of Fall Allergies

Allergies may be common, but they don't have to take over your life. Understanding what triggers your symptoms can help you feel better during the fall. Be sure to:

• Check the pollen count.
• Use allergy medications as directed.
• Seek care when symptoms persist.

With the right plan in place, you can enjoy crisp autumn days — without the sneezing.