How Long Does Allergy Season Last?

Find out how long you can expect to sneeze and wheeze your way through the year

Spring is always a time to celebrate as you move out of the dark, cold winter and into longer, sunnier days. But with the change of seasons comes the arrival of allergies and for some people, it feels like they don’t relent until months later, when a chill hits the air again.

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According to allergist-immunologist David M. Lang, MD, the various allergy seasons stretch for much of the year.

“Tree pollen season is usually at the beginning of spring in March, April, and the first half of May while the grass pollen season is typically mid-May through early-to-mid-July,” he says. “And the ragweed season is usually from mid-August until that first frost.”

He adds that the calendar can vary year to year, depending on meteorological conditions. For instance, a cold and wet spring can delay the tree pollen season and cause it to overlap with the peak of grass pollen season, causing a double whammy for allergy sufferers.

Daily weather can also affect pollen counts on given days. “Rain washes pollen from the air, so rainy days tend to be days with lower pollen counts,” Dr. Lang says. “Conversely, warm and breezy summer days typically have higher pollen counts.”

Mold spores, more problems

Besides pollen, patients may also become sensitized to airborne mold spores.
“Molds are much more numerous in ambient air than pollens,” Dr. Lang notes, “and there are molds that are present in high amounts in damp, rainy conditions. More importantly, though, warmer weather can be a particularly bad time for mold.

“There are molds that peak on days of maximum heat and humidity. So later in the summer, particularly from mid-July to early-September, is when the mold count gets very high,” he says.

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This can make a bad combination for many people who are allergic to both one or more pollens and molds. “That’s a common pattern,” Dr. Lang says, “that people will have these symptoms year-round and have a peak of symptoms in the spring and summer.”

Many of the patients Dr. Lang sees, he says, are polysensitized, or allergic to multiple allergens. “Sometimes we’ll see people with classic symptoms of rhinoconjunctivitis (nasal and eye symptoms) that occur seasonally – such as mid August through the frost, and we know it’s likely from ragweed.”

“But, more frequently, we see people with year-round symptoms and there are peaks in the warmer times of the year. But then we may find on skin testing they’re sensitized to pollens and molds, as well as dust mites and cat or dog dander.”

Geographic differences

Complicating matters a bit further is where you’re at geographically. For instance, in California, Bermuda grass is the major pollen allergen that triggers symptoms and ragweed isn’t an issue.

And in Texas, it’s mountain cedar trees. “The cedar trees there pollinate early in the year, in January and February and they can have much higher counts of tree pollen in the air than we would have in Northeast Ohio.”

How to cope

While allergies can make you feel absolutely miserable, it doesn’t have to always be that way. Dr. Lang recommends a combination of avoidance and medication. For instance, closing the windows of your house (and your car when driving around) and using your air conditioner can greatly reduce the amount of pollen indoors.

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Medication is also hugely important in helping to manage symptoms and keep you focused even when those pollen counts get high.

Intranasal steroids

“Intranasal steroids are the most effective medication for dealing with allergies,” says Dr. Lang. Available over-the-counter, Rhinocort, Nasacort and Flonase are intranasal steroids and are effective and safe to use.


Another effective measure against allergies, says Dr. Lang, are oral antihistamines. “If you’re going to take an antihistamine,” he advises, “you should take one that’s either non-sedating or low-sedating.” These, called second-generation antihistamines, include Claritin, Allegra, Zyrtec and Xyzal.

Allergists and allergy shots

If these don’t work, though, Dr. Lang assures us there’s still hope. “If you’re experiencing a level of symptoms that interferes with your desire to pursue activities or your symptoms are interfering with work or school performance, causing sleep disruption or sleep impairment despite avoidance measures and regular medications, you should see an allergist,” he says.

He also adds that allergy shots, called allergen immunotherapy, are also an option for properly selected patients. “The allergy shots offer the potential to affect the underlying allergic potential that drives symptoms.”

With so many Americans suffering from seasonal allergies, Dr. Lang encourages patients to seek out the right combination of remedies that can help them, including seeing an allergist. “We frequently see patients who are suffering needlessly and we can help.”

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