In short
- Children usually breathe through their mouth because something blocks the nose, such as enlarged adenoids or tonsils, allergies or a deviated septum.
- Cleveland Clinic says mouth breathing in children can affect their growth and behavior and may change the shape of their face.
- A 2021 meta-analysis of 10 studies linked mouth breathing in children to differences in jaw position, front teeth and airway size.
- Frequent snoring, breathing problems at night, daytime sleepiness and behavior problems can be signs of sleep apnea in children. Tell your pediatrician.
- While you wait for an appointment, saline drops or spray and a cool-mist humidifier can ease a stuffy nose.
- Mouth tape is not for children. The fix is finding and treating whatever is blocking the nose.
If your child often breathes through their mouth, especially while asleep, it's worth having their pediatrician check their nose and airway. Children usually mouth breathe because something is blocking the nose, and over time mouth breathing in children has been linked to changes in face shape, teeth, sleep and behavior.
Mouth tape is not for children. Whatever the cause turns out to be, the answer is to find it and treat it, not to keep your child's mouth closed.
Why do children breathe through their mouth?
Cleveland Clinic explains that most people breathe through their mouth because they can't get enough air in through their nose. In children, common causes include swollen or infected adenoids or tonsils that block the airway, nasal congestion from allergies, colds or chronic sinusitis, a deviated septum, and swollen turbinates (structures inside the nose that moisten and clean the air).
Cleveland Clinic also notes that children with chronic nasal congestion are more likely to develop mouth breathing, and that it can become a harmful habit.
How common is mouth breathing in children?
Mouth breathing in children is more common than many parents expect. The authors of a 2021 meta-analysis in BMC Oral Health cite studies estimating that mouth breathing affects between 12% and 55% of children. The wide range reflects how differently studies define and measure it.
In the 10 studies they pooled, which covered children aged 2 to 14, enlarged adenoids or tonsils were the most studied cause, in 6 of the 10. Two studies looked at children with sleep apnea and one at chronic allergic rhinitis.
What are the signs of mouth breathing in children?
Cleveland Clinic lists these common symptoms of mouth breathing:
- Bad breath
- Drooling when asleep
- Dry mouth
- Feeling tired all the time
- Hoarseness
- Snoring
You may notice your child sleeps with their mouth open, or wakes up with a wet pillow. Cleveland Clinic adds that a restless sleeper or a child who snores could be having trouble breathing through their nose.
It can help to watch your child for a few nights before the appointment. Note whether their mouth is open while they sleep, whether they snore and how loudly, and whether you ever hear pauses or gasps. A short phone video of their breathing can be useful to show the doctor.
Why does mouth breathing matter in children?
Cleveland Clinic says mouth breathing in adults isn't a serious health issue, but in children it can affect growth and behavior. It describes a "mouth breathing face", where a child's face may be narrow, they may have a receding chin or jaw, and their upper and lower teeth may not line up.
On growth, Cleveland Clinic is careful. It says mouth breathing isn't directly responsible for growth problems, but that the blocked airway behind it may be. It notes research suggesting that airway problems in children can keep the pituitary gland from releasing enough growth hormone.
On behavior, it says some experts believe children who mouth breathe may have sleep apnea or other sleep problems, and that the lack of sleep can make them irritable and restless, with behavior that can look like ADHD.
What does the research say about face and jaw development?
Research: moderate (what this means)A 2021 systematic review and meta-analysis in BMC Oral Health combined 10 studies comparing mouth-breathing and nose-breathing children under 18. Mouth-breathing children tended to have their upper and lower jaws rotated backward and downward and a steeper bite plane. Their upper front teeth tended to tilt forward, and narrowing of the airway was common.
These studies compare groups of children rather than following one child over time, so they show a link rather than proving mouth breathing alone caused every difference. The authors also note that age, sex and the cause of mouth breathing may confound the results. Even so, they conclude that removing the cause, and early orthodontic treatment where the bite is affected, can improve children's quality of life. We go into the dental side in mouth breathing and teeth.
Is mouth breathing a sign of sleep apnea in children?
HealthyChildren.org, the parenting site of the American Academy of Pediatrics, lists these possible signs of sleep apnea in children: frequent snoring, problems breathing during the night, sleepiness during the day, difficulty paying attention, and behavior problems. It says to let your pediatrician know right away if you notice any of them.
It explains that large tonsils and adenoids may block a child's airway during sleep, causing them to snore and wake often during the night. Not every child with large tonsils and adenoids has sleep apnea, though. Other risk factors it lists include overweight or obesity and conditions such as Down syndrome, cerebral palsy or craniofacial abnormalities. HealthyChildren.org says untreated sleep apnea can lead to heart, behavior, learning and growth problems.
Babies are a bit different. HealthyChildren.org describes periodic breathing of infancy, where a baby pauses in breathing, then breathes quickly to catch up, then goes back to normal. It's generally considered normal, and babies should outgrow it by 6 months.
Call 911 or your local emergency number if your child's breath stops for more than 20 seconds, if their skin turns pale, bluish or grayish, or if there's a change in muscle tone or they have a fever or other signs of illness.
Who should you see, a doctor or a dentist?
Start with your child's pediatrician. Cleveland Clinic advises asking them to check your child's nose and airway if you notice your child often breathes through their mouth. They can look for the cause and refer you to a specialist if needed.
Because mouth breathing is linked to how the teeth and jaws line up, it's also worth mentioning to your child's dentist at their next checkup. They can tell you whether an orthodontic opinion makes sense.
What happens at the appointment?
Cleveland Clinic says a healthcare provider will do a physical exam and look inside the nose and throat. They may also use a few simple checks:
- A lip seal test, to see whether your child can breathe comfortably with their mouth closed.
- A mirror test, where a mirror is held under the nose to look for clouding from breath coming out of the nostrils.
- A water test, where your child holds water in their mouth so they have to breathe through their nose.
If sleep apnea is a concern, HealthyChildren.org says your pediatrician may recommend an overnight sleep study called a polysomnogram. Your child sleeps in a specialized lab with sensors that track breathing, oxygen levels and brain waves. An ear, nose and throat doctor or a sleep specialist may help with the diagnosis.
How is mouth breathing in children treated?
Treatment for mouth breathing in children depends on the cause. Cleveland Clinic lists antihistamines or steroid nasal sprays for allergies, antibiotics for a sinus infection that lasts more than 10 days, and surgery such as removing swollen adenoids (adenoidectomy) when they block the airway.
For sleep apnea, HealthyChildren.org describes removing the tonsils and adenoids as the most common and effective treatment. It also says to schedule a follow-up visit afterward, because the operation doesn't always work. CPAP, a machine that delivers steady air pressure through a mask, is another option for children whose sleep apnea continues after surgery or who can't have it.
What can you do at home in the meantime?
You can make a stuffy nose more comfortable while you wait for an appointment. The Sleep Foundation suggests saline nasal spray or drops to loosen mucus, and a cool-mist humidifier to add moisture to the air and soothe irritated nasal passages.
For older children, a saline rinse may be an option. The FDA says some children are diagnosed with nasal allergies as early as age 2 and could use a nasal rinsing device if a pediatrician recommends it, though very young children might not tolerate it. If you do use one, the water rules matter, and how to use a saline rinse explains them.
The Sleep Foundation advises seeing a pediatrician if your child's congestion lasts more than a few days, comes with a high fever, or affects their ability to eat or sleep. Cleveland Clinic suggests keeping an eye on stuffy noses in general, since treating chronic congestion can help stop mouth breathing becoming a habit.
Can children use mouth tape?
Children shouldn't use mouth tape. Mouth tape is for adults only. A child who breathes through their mouth usually can't breathe well through their nose, and taping the mouth doesn't fix that. Read mouth tape for kids for more on why we don't recommend it, and see our safety page for who shouldn't use mouth tape at all.
If you're an adult who mouth breathes at night yourself, the picture is different, and why do I breathe through my mouth at night? is a good place to start. If you want to understand why nose breathing matters in the first place, nasal breathing vs. mouth breathing covers the basics.
Common questions
Is it normal for a child to breathe through their mouth while sleeping?
Mouth breathing now and then, for example during a cold, is common. If your child often breathes through their mouth or snores, Cleveland Clinic advises asking their pediatrician to check their nose and airway.
Can I use mouth tape on my child?
No. Mouth tape is not for children. A child who breathes through their mouth usually has a reason, such as enlarged adenoids or allergies, and that needs a doctor's assessment.
Can mouth breathing affect a child's teeth?
It can. Cleveland Clinic says a child's upper and lower teeth may not line up, and a 2021 meta-analysis found mouth-breathing children tended to have their upper front teeth tilted forward. Mention it to your child's dentist as well as their doctor.
When is a child's breathing at night an emergency?
HealthyChildren.org, from the American Academy of Pediatrics, says to call 911 if your child's breath stops for more than 20 seconds, if their skin turns pale, bluish or grayish, or if there's a change in muscle tone or they have a fever or other signs of illness.
My baby pauses when breathing during sleep. Is that sleep apnea?
Not necessarily. HealthyChildren.org describes periodic breathing of infancy, where babies pause and then breathe quickly to catch up. It's generally considered normal and babies should outgrow it by 6 months. Talk to your pediatrician if you're unsure, and call 911 if a pause lasts more than 20 seconds.
How common is mouth breathing in children?
Estimates vary widely. A 2021 meta-analysis cites studies putting it at between 12% and 55% of children.
Can a child use a saline rinse for a blocked nose?
Sometimes. The FDA says some children are diagnosed with nasal allergies as early as age 2 and could use a rinsing device if a pediatrician recommends it, though very young children may not tolerate it. For a stuffy nose, the Sleep Foundation suggests saline spray or drops.
Is snoring in children a sign of sleep apnea?
It can be. HealthyChildren.org, from the American Academy of Pediatrics, lists frequent snoring as a possible sign of sleep apnea in children, along with problems breathing at night, daytime sleepiness, trouble paying attention and behavior problems. It says to let your pediatrician know right away if you notice any of these.
Sources
About this article
- Research
- 5 published sources, listed above.
- Evidence
- Moderate. How we rate it
- Last checked
- October 10, 2026
- Funding
- Paid partner of Titan Recovery. Their ads are labeled.
- Found an error?
- Tell us. We log fixes on the corrections page.
* This content is for informational and educational purposes only and is not medical advice. It is not intended to diagnose, treat, cure or prevent any disease or health condition. Talk to a qualified healthcare provider about your health.
