Q: I always get sneezy and congested around the holidays. Is my Christmas tree to blame?
The holiday season can be a time filled with joy, mirth and — sometimes — itchy eyes, irritated skin, congestion and wheezing. This cluster of symptoms, sometimes referred to as “Christmas tree syndrome,” typically doesn’t stem from an allergy to the Christmas tree itself.
But sometimes certain hitchhikers on the tree, like mold or dust, can cause an allergic reaction, experts say. And if you’re sensitive to the tree’s fragrance or sap, that can also irritate your skin or airways.
Thankfully, there are ways to minimize the risk that your Christmas tree will turn you into a sneezing, sniffling Scrooge.
What are the potential triggers?
Typically, when people are allergic to trees, they are allergic to their pollen — the powdery substance that plants produce during reproduction.
But evergreen pollens are less likely to induce an allergic reaction than other tree pollens, and trees don’t usually produce pollen around this time of year, so it’s unlikely that a person would be truly allergic to their Christmas tree, said Dr. Joshua Davidson, an allergist and immunologist in Redondo Beach, Calif.
That said, you could still experience allergic or allergy-like reactions when spending time with your favorite pines, spruces and firs. Here are some potential causes.
Mold. Certain types of mold can grow on a Christmas tree. And if you’re allergic to that mold, bringing a tree into your home can cause allergy symptoms, Dr. Davidson said. In one 2023 study, researchers analyzed the results of allergy tests administered to more than 1.6 million people in the United States between 2014 and 2019. They found that nearly 17 percent of them showed an allergy to Alternaria alternata, a common type of mold that can grow on Christmas trees.
Unfortunately, the mold is so small that you can’t see it with the naked eye, said Dr. Sanjiv Sur, an allergist and immunologist at the Baylor College of Medicine in Houston. But if your Christmas tree was growing in rainy or humid conditions before it was cut, he said, mold is more likely to be present. Mold may also grow more easily if the tree is stored or transported in an unventilated, damp space, or if it’s kept next to other trees and mold transfers between them, Dr. Sur said.
Fragrance. Although many people love how Christmas trees smell, their scent — which comes from chemicals called terpenes — can also cause problems. In fact, Dr. Davidson said, anything with a strong fragrance can be an irritant. “It’s not really an allergy, but it’s just irritating to the airway,” he said, and it can cause sneezing, congestion, itchy eyes and sometimes wheezing and chest tightness.
Sap. Touching your Christmas tree — and especially its sap or resin, a thick substance that trees release after injury — could irritate your skin, too, resulting in itching or a rash, Dr. Sur said. If the tree’s needles poke you, that may also cause irritation or a rash, Dr. Davidson added.
Dust and other debris. If your tree is grown in a dusty area, or transported through one (like a dirt road or construction site), it may bring dust into your house, Dr. Sur said. If you have an artificial Christmas tree, you may not be in the clear, either. People usually aren’t allergic to fake Christmas trees, but because the trees are often stored for much of the year in dirty lofts or storage spaces, they can easily accumulate dust mites and mold, said Dr. Linda Cox, an allergist in Fort Lauderdale, Fla.
“This has happened to many of my patients,” she said. After coming in with bad asthma attacks, they’ll often say that they were triggered after they climbed into their attics and unpacked their tree.
How can you manage the symptoms?
If you’re experiencing respiratory symptoms around your tree, air purifiers containing HEPA filters can help by removing mold and other irritants from the air, Dr. Cox said.
You can also try to kill any mold that might be lurking on your tree, Dr. Sur said. Mold needs humid conditions — at least 55 percent relative humidity (a measure of how much water vapor is in the air relative to its temperature) — to grow. If you’re having allergy symptoms and your air feels muggy, try running a dehumidifier. You can also purchase a hygrometer, which measures relative humidity, for less than $15, he said.
Dr. Davidson said you could also take decongestants to alleviate your symptoms.
If you develop skin irritation after touching your tree, try creating “a barrier” between your skin and the tree by wearing long sleeves and gloves the next time you need to touch it, Dr. Sur said.
When putting up a potentially dusty or moldy artificial Christmas tree, consider wearing a mask, like an N95, that can filter out dust while you’re moving or assembling it, Dr. Cox suggested.
And if nothing else, remember that any suffering you experience will be short-lived — much like the holiday season. “It’s just a few weeks,” Dr. Sur said. “In January, it should all disappear.”
