Dermatologists reveal the gross reason why you should wash your new Christmas pajamas before wearing them — especially if you have this condition

It’s Christmas Eve, and you know what that means: a feed taken over by corny snapshots of families draped in matching festive pajamas.

Whether you’re jumping on the trend or you’re expecting a certain relative to gift you another pair this year, it’s safe to say that Christmas-themed jammies are becoming quite the tradition.

However, if you’re not planning on wearing pajama sets previously worn last Christmas, the pjs you’re getting this year are brand spanking new…and probably unwashed.

I know what you’re thinking. But they’ve never ever been worn, so what’s the point in washing them?

Well, it turns out that those fresh pair of pajamas under the Christmas tree really aren’t that fresh. In fact, they really need to be cleaned before the sugar plum fairies can even think of dancing in your head.

To understand why it’s important to clean new pajamas before wearing them, I spoke to three dermatologists: Dr. Julie de la Cruz of Miami Dermatology & Surgery, Dr Shamsa Kanwal of Aesthetic Evolution Skin and Laser Clinic, and Dr. Tanya Kormeili at the Derm & Rejuvenate Institute.

Here’s what they had to say about the risks of wearing unwashed new pjs, who’s most at risk and how to wash new pajamas to ensure they’re festively fresh.

Why should you wash new pajamas before wearing them to bed?

While we like to think that a newly unboxed pair of pajamas are just as fresh as they look, the truth is that they don’t arrive at the store or doorstep spotless. In fact, you shouldn't sleep in unwashed new pajamas for the same gross reason why you should wash new bed sheets before sleeping on them.

According to dermatologist Dr Shamsa Kanwal, new pajamas carry remnants of finishing chemicals, dyes and allergens (such as dust) from the warehouse.

“Washing once removes a lot of that surface residue and lowers the chance of itching, rash, or contact dermatitis, especially if you have sensitive skin or eczema,” advises Dr Kanwal. “It also softens the fabric, which reduces friction on the skin.”

Dr Tanya Kormeili agrees. “Chemical residues, dyes and microscopic debris consist of formaldehyde resins, disperse dyes, oils and even bacteria from shipping and packaging, so washing off the irritants, allergens and microbial agents is a good idea!” says the board-certified dermatologist, professor and medical consultant.

As Dr. Julie de la Cruz explains, newly-made pajamas are treated with skin-irritating chemicals in order to prevent the growth of mildew and mold in transit and to make the material “wrinkle-free”, plus there’s they're likely to be passed around a lot before they make it under your Christmas tree.

“By the time your pajamas go from the manufacturing factory to the store to your home, they have passed through several different hands and have picked up dust, dirt and germs,” de la Cruz warns.

How can wearing unwashed new pajamas affect sleep?

So, how can a pajama set plagued with chemicals and allergens get in the way of a good night’s sleep?

“Because pajamas sit directly against large areas of skin for 7–9 hours, even small irritants can have an outsized effect on sleep quality," explains Dr Kormeili.

According to Dr de la Cruz, these small irritants can spark an allergic reaction. “Sleep can be affected if the allergens (such as dust and germs) and excess chemicals on the pajamas cause allergic flares and skin irritation from allergic or irritant contact dermatitis,” warns the board-certified dermatologist.

Dr Kanwal also points out that its not just the new pajama set's chemical residues that can cause a rash.

"If the fabric is still stiff, it can cause a subtle itch, warmth, or prickling that keeps you tossing or waking up," says the board-certified dermatologist with over 10 years of clinical experience.

"For people with eczema, allergies, or very reactive skin, it can trigger a flare that makes sleep harder and scratching more likely."

How bad is it to wear unwashed new pajamas for only one night?

"How bad it is depends on the level of skin sensitivity you have," explains Dr de la Cruz. "For instance, someone with eczema and allergies would be more effected than someone who does not."

"For many people, one night is unlikely to cause major harm," agrees Dr Kanwal. "The risk is higher if you have eczema, fragrance sensitivity, or a history of rashes from fabrics or detergents, because even one night can trigger redness or itch. If you notice irritation, wash them before wearing again and moisturize the skin."

While many people without sensitive skin won't be at risk if they wear their new pajamas straight from the packaging, Kormeili advises they don't make it a habit.

"It is unlikely that one unwashed pajama set will cost you a night of sleep," says Dr Kormeili. "However, toxins over time do affect your hormones and organs, and sleep can be affected due to toxic bodies."

"PJs are on you for 6-9 hours (depending on how much sleep you need) and have ample time to take effect, especially when you are sweating and your skin pores are open, or very sensitive skin may develop itching or redness that prevents deep sleep."

How should you wash new pajamas?

You'll be pleased to know that it doesn't take a thorough clean to remove chemicals and allergens from new pajamas.

"When it comes to what wash cycle to choose for washing new pajamas, I recommend following the instructions indicated on each individual garment," says de la Cruz. "Different materials call for different laundry instructions."

"I usually suggest a warm wash on a normal or gentle cycle with a fragrance-free detergent, followed by a full rinse," Dr Kanwal tells me. "For very sensitive skin, add an extra rinse and avoid fabric softeners or scented dryer sheets. For delicate fabrics, use cold water and a delicate cycle, but still do that first wash before sleeping in them."

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