Here’s what you need to know about the 2018 allergy season

Let the itchy eyes and sneezing begin.

Cambridge, MA 042611 Cherry trees framed a pair of joggers as they ran along the Charles River in Cambridge, Tuesday, April 26 2011.(Globe Staff Photo/Wendy Maeda) section: Metro slug: 27feature reporter: In-Cap Wendy Maeda / The Boston Globe

The sun is shining, the temperature is rising, and trees along the Charles River are bursting into bloom — heralding the start of the 2018 allergy season.

And if you’re already starting to cough, sneeze, or have itchy eyes from the pollen floating around, you may be in for a rough few weeks.

To learn more about how long the allergy season will last, where you can track pollen counts, and what you can do to survive — and prevent — symptoms we turned to Dr. Maria Castells, an allergist and immunologist at Brigham and Women’s Hospital.

She says residents in the Boston area who experience seasonal allergies should expect a “severe year.”

“People need to be aware that in the next couple weeks, as soon as the temperature hits the 60s or even the 70s, there is going to be a high pollen count in the air,” she said.

Why this year is expected to be bad

Castells said the pollen season is dependent on the length of light and temperatures during the day.


“Pollination can be pushed back and forth by the fact that the light [is] increased but the temperature might not be very appropriate,” she said.

That’s what happened this year.

While the light may have changed in March and April, snow and ice were still present in the region a few weeks ago.

“The pollen was ready to go in the air but that was not allowed because of the low temperature,” Castells said. “So what we will be seeing this pollen season is a burst of pollen.”

In the Boston area, she said pollen will continue to be released in bursts — rather than a continuum of a few grains — from trees over the next few weeks.


Because of the temperature changes seen this spring, one day may see thousands of pollen grains released in the morning and the next day could see none.

“It’s going to be a pretty severe year because [there have] already been several bursts of pollen out there that have been in between days where the temperature has gone down, so pollen is not being released in the air,” Castells said. “And there will be very few bursts in the next week or so. There is a lot of pollen from the trees that have not been released and will continue to be in the air.”

When the pollen season will end

Pollen season begins in the spring — usually at the end of March or the beginning of April — when trees begin to release the tiny grains in the air. Tree pollen is followed by the release of grass pollen — which occurs from May into July — and by weeds rounding out the year by releasing the tiny irritants in the fall.


“There is a continuum of a pollen season that starts in the beginning of the spring till the fall,” Castells said.

People who are allergic to all three types of pollen — tree, grass, weed — face a more difficult and prolonged season and should see a specialist to discuss treatment options, she said.

“Monitoring each patient’s season is the most important thing — when is it that the symptoms are the worst,” Castells said. “Some people are just allergic to the tree pollen, some people to the grass pollen, some people to the weed pollen.”

Those only sensitive to the pollen from trees can expect four to six weeks where their symptoms will be bad. For those impacted by grass pollen it would be another four to six weeks, she said.

How pollen count is measured and where you can track it

Castells recommends seasonal allergy sufferers monitor pollen measurements, called a “pollen count,” in order to help prevent and treat symptoms.  


To get the count, airborne pollen deposits are measured in the morning mechanically by devices in tall buildings, with the higher number of grains associated with the a “high amount of symptoms in people who are allergic,” she said.

The American Academy of Allergy and Asthma and Immunology posts pollen counts for New England based on readings in Waterbury, Connecticut, but Castells said it is also worth checking local sites for the pollen forecast at the beginning of the week and daily if needed.

Typically, she said, pollen grains are higher in the early morning — starting around 4 or 5 a.m. and will go down in the afternoon.

What you can do to survive the allergy season

According to Castells, the best way to prepare for allergy season is to know what pollen you’re sensitive to — either based on previous experience or by seeing an allergist and having a plan for the medication you can take on a daily basis.


“Once one knows ‘what are the specific allergies,’ [they will be] much better prepared for taking the medication that’s pointing to the forecast,” she said.

Castells said the “most dangerous time of the day” is the early morning, so during high pollen season allergy sufferers should plan any outdoor activities or exercise for the afternoon — around 5 or 6 p.m. — when the pollen is settling.

Keeping your windows shut while you’re sleeping can also help prevent irritation.

“I know that’s hard now that we’ve had a long winter, we’d love to have a little bit of air in the bedrooms, but that’s kind of dangerous because all the pollen grains starting at 4 and 5 a.m. start to come inside the bedrooms and start to inflame the nose, the eyes, the throat, the lungs,” Castells said. “Then when people wake up in the morning they start to cough, they start to feel like they can’t really sleep well, sneezing, and not being able to breathe through their noses.”


Rely on air conditioning if you need to cool down instead, she said.

People suffering from allergies should also make sure they have enough medication to treat the acute symptoms, as well as chronic symptoms they might have.

Castells said if you start to feel the tell-tale itchy eyes or begin to cough and sneeze, don’t wait to treat the allergy symptoms.

“What will be most efficient for people with allergies is to try and start treating themselves now, not waiting until the pollen is very high,” she said. “When the pollen is very high the medications that can be taken — the antihistamines, the inhalers, the anti-inflammatory medications — actually can try and subdue and control the symptoms. But when the medication is taken beforehand it actually prevents the symptoms. So much milder symptoms occur if people take the medication before the actual pollen season.”