Warning of the allergic reaction sparked by Christmas trees

A warning has been issued for potential allergic reactions for Australians using a real Christmas tree in their homes this festive period.

Christmas tree syndrome is an allergic reaction to Christmas trees due to the grass, tree and weed pollens stuck on the tree spreading inside the home.

National Asthma Council Australia spokesperson Professor Sheryl van Nunen said the pollens get stuck to the pine trees while they're growing and then when the tree is brought into the house and begins to dry out, the pollen spreads.

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Asthma and allergy sufferers can then have an allergic reaction to the pollen circulating in their homes.

An allergic reaction will be the usual symptoms, van Nunen said, like sneezing, running nose, cough and wheezing.

But van Nunen said it's easy to avoid.

"Simply hose the tree down outside before you bring it in," she said.

"Then cut 2.5cm off the bottom so you can water the tree and (it) will stay in a reasonable condition without drying out too quickly, but remember not to try that with electric lights.

"Don't keep it in the house too long.

"Make sure to take the Christmas tree out before the 12 lords a-leaping arrive."

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Not only do real Christmas trees pose a risk to asthma and allergy sufferers, but artificial trees could be carrying allergens.

"Artificial trees can accumulate dust and mould, depending on how they're stored, most of us have a Christmas tree for many years," van Nunen said.

But like real trees, there are a few simple steps to prevent an allergic reaction.

"With an artificial tree all you need to do is inspect it outside and inspect for mould, send the non-allergic person on the family on this mission, then give it a good shake and wipe it over and you'll have a healthy artificial tree," she said.

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van Nunen said asthma sufferers, of which there are 2.7 million in Australia, should also always take their preventative measures with them in case another household's Christmas tree hasn't been checked.

"It's holiday time, our asthma people just need to remember to take their relieving agent with them so if they turn up at someone's house who hasn't hosed off their tree and they have Christmas spoiled by symptoms," she said.