So Your Kid Has A Gross Rash Around Their Mouth. What Do You Do?

At some point in 2021, my kid developed a stubborn rash — a bright red, perfectly round circle around her mouth. She was wearing a mask to school at the time, and she'd developed a habit of licking around her mouth underneath it. The doctor confirmed it wasn't impetigo. It wasn't really bothering her, either, though sometimes I made it worse by attempting to solve it with various moisturizers we had lying around the house. But it frustrated me — here she was with this bright red circle around her mouth, and I couldn't make it go away.

Well, it turns out she's not the only one, and there's actually a term for this specific rash: lip licker's dermatitis.

"It's not uncommon whatsoever, especially in our toddler and early school age kids," confirms Dr. Nicole Harter, a board-certified pediatric dermatologist at Children's Nebraska Omaha, an associate professor of dermatology at the University of Nebraska Medical Center, and a member of the Society of Pediatric Dermatology. And it's exactly what it sounds like: inflamed and irritated skin around the mouth due to lip licking.

"Kids stick their tongue out and run this rim up and around their upper and lower lips," Harter says. "So you see this perfect circle. It looks like somebody took a toilet paper tube and covered their lips and drew with a red marker." Though it depends on the underlying skin tone — on darker skin, it might look dark brown or purple.

Harter explained a little bit about why this happens and, most importantly, what you can do about it.

What causes lip licker's dermatitis?

Harter explained that there are really two parts of your lip, and they're both delicate. "There's what we call the wet mucosal lip, the pink part of our lips," she explains, "and what we call the cutaneous lip, which is the skin area surrounding the lip." The whole area dries out — especially in the winter — and your first impulse is to lick your lips.

"Well, you just exposed your lip to moisture and the irritating salivary enzymes in your saliva. Then that moisture rapidly evaporates and takes another layer of moisture with it," says Harter. Boom... vicious cycle. "Every time you lick your lips, it then dehydrates further, and it gets worse and worse." Kids are even more prone to this type of irritation because they don't understand the counterintuitive fact that spit makes the problem worse, and let's face it — what 4-year-old wants to step away from their game for anything, much less lip balm?

Until you break that cycle, the rash gets worse. It gets redder, more textured, and scalier. In some cases, itchy skin or cracks and fissures can also develop, creating an open wound that renders your kiddo's skin vulnerable to infection.

There are also things that'll further irritate the skin, or at least make it look worse. I noticed that tomato-based foods (i.e., ketchup and tomato sauce, two core pillars of her diet at the time) tended to make my kid's rash particularly livid looking. Turns out acidic foods like citrus fruits and vinegar-based foods like ketchup and salad dressings can be irritating and make the existing inflammation sting and look even redder.

Who gets lip licker's dermatitis?

Any kid can get lip licker's dermatitis. "It's common in toddlers and young kids because they're not going to stop whatever they're doing — they're busy, they're playing, they're in school — to put on a lip moisturizer," says Harter.

But some kids are especially predisposed — specifically, kids with underlying atopic dermatitis or eczema or whose parents have those conditions. Kids with an underlying tendency to allergic reactions are also prone, meaning kids with asthma, seasonal allergies, or hay fever.

In my kid's case, she's definitely a sensitive-skinned girlie. Before potty training, we were in a constant battle against diaper rash. Name a cream, I tried it. Her skin also dries out in the winter, and wherever she scratches, she gets red, raised skin. Sure enough, I have asthma and sensitive skin, and her dad has sensitive skin, too. Sorry, kid.

If your kid gets a lip licker's dermatitis rash and tends to have red, textured patches or itchy skin generally, it might be worth flagging the child to their doctor during your next routine visit and asking how to address skin sensitivity.

What else should you rule out?

There are some other skin conditions you might want to eliminate from consideration while figuring out your next moves. For instance, daycare was totally reasonable in insisting we check with a doctor that my kid didn't have impetigo, a contagious bacterial infection that would have been a real pain for them to deal with.

You should also rule out cold sores and something called angular cheilitis, which manifests as scaly cracks or bumps in the corners of the mouth. But neither forms that distinctive round rash.

Another thing to consider? Allergic contact dermatitis, an allergic reaction to something applied to the skin. "You could have been using the same lip balm your whole life, actually, and your body's immune system decides it's no longer tolerating it ... now you're developing that allergic reaction every single time you put it on," elaborates Harter.

What can I do?

Think simple. "Get a thick, bland moisturizer, something using petrolatum, like Vaseline," says Harter. "That's going to restore a moisture layer and provide a layer of protection from the outside world." You'll often have to reapply it several times throughout the day, she warned.

Important to know: A lot of the products out there that are supposedly designed to moisturize lips might actually make the problem worse. "Any lip emollient that is not completely basic pure petrolatum can create irritation, especially with fragrances or other active ingredients," Harter explains. "I would say a lot of the brand-name lip moisturizers out there — designed, per se, to treat lip inflammation — will actually make things worse and not better." The times I managed to make it worse, I probably used products that contained irritants like fragrance or "soothing" menthol.

What finally worked for us was a strict but simple regimen. Every night before bedtime, we wiped my daughter's face with the same type of baby wipes we used back in her diaper rash era (unscented WaterWipes) and then covered her face with some sort of heavy-duty occlusive balm like Aquaphor. Yes, I basically taught my child slugging. It takes a couple of weeks, but if we're diligent, that usually sorts her out.

But for your kid, kicking the rash might require a topical anti-inflammatory medication, "usually a topical steroid or non-steroidal ointment," Harter says. There are over-the-counter and prescription versions that you'd apply before your petroleum jelly product.

When’s it time to see a doctor?

In an ideal world, you'd pop over to the doctor's office whenever you had a question or concern. But we don't live in an ideal world, and work and school schedules are a thing. So when do you make the appointment? "A big turning point is the level of symptom of the child," says Harter.

If you've got a toddler who's still at home (and therefore wouldn't have picked up impetigo somewhere), who's playing normally and doesn't really notice the rash, you can probably treat the dermatitis at home. If you've got a kid who's distracted and uncomfortable or in pain, that's when you want to check it out. Your child's pediatrician can ensure there's no infection and discuss whether you need something more than Aquaphor and a simple over-the-counter topical ointment.

"I think it's especially salient for school-aged kids — if they're distracted during their school day and their teacher is concerned they're not paying attention, or if they can't pay attention because they're complaining that their lips hurt or they don't want to eat or drink," says Harter, "that would be a time to escalate the level of care."