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What to expect from allergies throughout the year

Digital writers

Friday, May 4, 2018, 1:30 PM - For the allergy-prone, the arrival of warmer weather can sometimes be treated with an air of resignation. Though the warmth is welcome, the runny nose and watery eyes aren't.

But there are ways to get ahead of this annual bout, starting with paying attention to the calendar for signs of each of the three documented waves of pollen allergens. 

Dr. Susan Waserman, a professor of medicine at McMaster University’s division of clinical immunology and allergy, says it usually begins with tree pollen, emerging by early April in most places, though the actual start date varies depending on the weather and moisture in your part of Canada.

“That’s usually the first pollen to emerge, and now with the temperatures increasing, we already have some in the air,” Waserman told The Weather Network.

Tree pollen season can last all the way until June, followed in quick succession by grass pollen season, which can begin as early as mid-May and runs through into July. Ragweed pollen is the last stage, beginning mid-August and peaking more or less around Labour Day, though traces of it can last until the first frost.


When the winter comes, there’s little to fear from external pollens, but the year-round allergens inside your own house, such as dust mites, moulds and pet dander, can seem more acute during the coldest season.

“We tend to not ventilate as well in the winter, the house is more sealed up, so certainly for those year round allergies, people can be symptomatic all year round, even in the winter,” Waserman says.

Though the allergens are being produced by different sources depending on the time of year, Waserman says they’ll each have more or less the same effect -- the usual symptoms like runny nose, itchy and watery eyes, post nasal drip, congestion, and sinus pain and pressure.

“They tend to be not that different in terms of the types of symptoms that emerge, but across the country, depending on what you’re allergic to, you may have different trees that come out earlier in B.C., for instance,” she says. “So the time of year that you start to react, and the severity, will differ geographically, but the symptoms tend to be similar.”

Perennial allergens: Present all year, people become acclimatized to symptoms, so may not recognize them as bothersome compared the the more sudden onset of pollen.

“Once you get used to always being congested, like with dust house mites, people tend to build up an almost insensitivity to the symptoms, they’re just not as explosive as the seasonal pollens,” Waserman says.

As for the symptoms, aside from preventative measures like using air conditioning to keep pollens out, the good news is medicines like antihistamines and intranasal steroid sprays work well across the board, regardless of what actually triggered the symptoms.


But Waserman says, by contrast, longer term remedies, such as allergy injections or tablets taken under the tongue, are allergy specific.

“You really do need to know what you’re allergic to to embark on those specific treatments, and for that you need to see your allergist to be skin-tested,” she says.

Whatever the trigger, and whatever remedy is best for the sufferer, Waserman stresses that allergies shouldn’t be ignored or dismissed as something to be simply endured, especially given their effects can last months.

“It’ll interfere with sleep, and sports, and concentration and work, so get it attended to. Do not suffer in silence,” she says.

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