Allergy Guides and Resources

Daily ranking of the US cities with the highest pollen levels right now. See where tree, grass, and weed pollen is hitting hardest today.

What drives spring tree pollen, which species cause the most symptoms in each region, and what you can do to manage your allergies from February through May.

Grass pollen takes over from May through July. Which grasses trigger symptoms, why mowing makes it worse, and how to handle heat, smog, and thunderstorm asthma all summer.

Ragweed drives fall allergies from mid-August through the first frost. Which weeds and molds trigger symptoms, when your region peaks, and how to manage it all season.

Mountain cedar pollen spikes December through February in central Texas. What cedar fever is, why it is not a real fever, how it differs from the flu, and how to get through the season.

Ragweed ends at the first hard frost, from early October in the north to December on the Gulf Coast. End dates by region, and why warmer falls keep pushing them later.

Rain knocks pollen out of the air temporarily, but counts often spike 24 to 48 hours later as plants rehydrate and release more. The full story of rain, pollen, and thunderstorm asthma.

Pollen counts follow a daily cycle. Tree pollen peaks mid-morning, grass pollen midday, and counts drop in late afternoon. Plan your outdoor time around the curve.

There is no single pollen season. Tree, grass, and weed pollen overlap from February through November. A full calendar breakdown by type and region.

Wind is the primary way pollen travels. Learn why windy days are worse for allergies, how wind speed changes your exposure, and what to do about it.

An honest look at quercetin, butterbur, stinging nettle, vitamin C, and bromelain. What the evidence says, what it does not, and when OTC is the better choice.

Zyrtec, Claritin, and Allegra all treat the same symptoms. The differences are how fast they work, how likely they are to make you drowsy, and one food quirk. How to choose.

Oak is the biggest driver of spring allergy misery across most of the US. Why it is so bad, when it peaks by region, and whether that yellow dust on your car is really oak.

Birch is the dominant spring tree allergen in the Northeast and Pacific Northwest, and the classic trigger for the itchy mouth of oral allergy syndrome. Season, symptoms, and foods that cross-react.

Light rain clears the air for an hour or two, but counts rebound a day later, thunderstorms can trigger sudden asthma, and damp leaves raise mold. The full picture.

You do not have to stop running in pollen season. The best times to go by trigger type, a pre and post-run checklist, and the breathing signs that mean stop and see a doctor.

Pollen is mostly cosmetic, but left on the paint it can etch the clear coat and scratch when you wipe it dry. How to wash safely in pollen season, and keep it out of the cabin.

Mowing throws grass pollen and mold straight into the air you breathe. The right time to mow, the mask that actually helps, and lawn habits that lower pollen over time.

Humid air bursts pollen into finer particles and grows mold and dust mites indoors. The ideal indoor range is 30 to 50 percent, and here is how to hit it.

A hard freeze near 28°F ends ragweed for the year, but one frost is not enough and trees pollinate through winter. When cold actually gives you a break.

Pollen on your hair and clothes, mucus pooling when you lie down, and bedroom dust mites all gang up after dark. The bedtime routine that quiets it down.

Keep them closed on high-pollen days and run the AC. Open up after rain, in the evening, and on low-count days. How to air out your home without the pollen.

Wet laundry on the line traps pollen and carries it back inside, onto your bed and towels. When to skip the line, and how to keep your wash clean.

Your dog carries pollen indoors on its fur and paws, and dogs get pollen allergies too. How to cut what they track in, and spot their own symptoms.

Camp, hike, and go to the festival anyway. Check the 5-day forecast, time your days around the morning peak, and pack for the pollen.

Itchy eyes and weeks of symptoms point to allergies. A fever and a 7 to 10 day arc point to a cold. A side-by-side comparison and how to treat each.

No. Despite the name "hay fever," pollen allergies do not cause a true fever. What a fever really points to, why allergies can feel feverish, and when to see a doctor.

Can Pollen Cause a Sore Throat?

Yes — post-nasal drip and direct airway inflammation from pollen are behind most allergy-season sore throats. Here's the mechanism and what actually helps.

Can Pollen Cause Hives?

Pollen can trigger hives and skin rashes through systemic histamine release and direct contact reactions. Learn which pollen types are most likely to cause skin symptoms.

Can Pollen Cause Itchy Skin?

Pollen causes itchy skin through histamine release, direct contact reactions, and eczema flares. Find out how to identify the pattern and stop the itch.

Can Pollen Cause Nosebleeds?

Pollen doesn't rupture blood vessels directly, but the inflammation and dryness it causes make nosebleeds far more likely during allergy season.

Can Pollen Cause Dizziness?

Pollen-driven congestion blocks the Eustachian tube and disrupts inner ear pressure, causing dizziness and lightheadedness during allergy season.

Can Pollen Cause Coughing?

Post-nasal drip and direct airway inflammation from pollen are behind most allergy-season coughs. Learn how to tell if your cough is pollen-related and how to treat it.

Can Pollen Cause Sneezing?

Sneezing is the body's most immediate response to inhaled pollen. Here's the science behind the reflex and how to stop it from taking over your day.

Can Pollen Cause Chest Pain?

Pollen causes chest tightness through allergic asthma and airway inflammation. Learn the difference between allergy-related chest symptoms and other causes.

Can Pollen Cause Styes?

Pollen drives the allergic eye itching that leads to eye-rubbing — the main way bacteria reach eyelid glands and form styes. How to break the cycle.

Can Pollen Cause Laryngitis?

Post-nasal drip, vocal cord inflammation, and throat-clearing from pollen allergies can cause hoarseness and laryngitis. How to protect your voice during pollen season.

Can Pollen Cause Fatigue?

Allergy fatigue is real. Histamine, broken sleep from congestion, and drowsy antihistamines all drain you. How to tell allergy tiredness apart and get your energy back.

Can Pollen Cause Ear Pain?

Pollen inflammation swells the Eustachian tube, causing ear fullness, popping, and mild pain. How to relieve the pressure and tell it apart from an ear infection.

Can Pollen Cause Headaches?

Pollen swells your sinuses and traps pressure behind your forehead and cheeks. That pressure is the headache. How to tell it from a migraine and clear it.

Can Pollen Cause Brain Fog?

Allergy brain fog is real. The immune response, lost sleep, and sedating antihistamines all cloud your thinking. Why it happens and how to clear your head.

Can Pollen Cause Swollen Lymph Nodes?

Not usually on their own. Lymph nodes swell to fight infection, not pollen, but allergies can lead to one that does. What your neck swelling really is.