Mouth Breathing

Mouth breathing is when people can’t breathe through their nose so they take in air through their mouths. Mouth breathing can cause sleep disorders that affect daily life. It also can change the structure of people’s faces. Healthcare providers treat mouth breathing by surgery or medication to enable people to breathe through their nose.


Mouth breathing causes top row left hand side: Enlarged tonsils and deviated septum. Second row left hand side: Enlarged adenoids and chronic stuffy nose from allergies, colds or chronic sinusitis. Mouth breathing symptoms top row left hand side: Dry mouth, bad breath and drool on pillow. Second row left hand side: Daytime sleepiness and malocclusion.
Mouth breathing can affect your overall health. Here are some physical conditions that cause mouth breathing. Here are some symptoms and signs you might notice if you’re mouth breathing.

Mouth breathing is when people rely on taking in air through their mouths and not their noses. Mouth breathing may be why some people wake up with dry mouths and drool on their pillows.

But mouth breathing causes more problems than soggy pillows and dry mouths. Mouth breathing can cause sleep disorders that affect daily life. It can also change the structure of people’s faces. Most people develop mouth breathing as very young children, potentially setting the stage for long-term problems.

What’s the difference between breathing through my nose or my mouth?

There are several differences between breathing through your mouth instead of through your nose:

  • When you breathe through your nose, tiny hairs called cilia filter out debris like allergens, pollution and even small insects. Your mouth doesn’t offer that protection.
  • Your lungs and throat function better with moist air. Your nose has bony structures called turbinates that handle that task. Air you take in through your mouth is drier.
  • Likewise, your throat and lungs thrive on warm air. When you breathe in through your nose, the air you take in gradually warms up until it’s closer to body temperature, making it easy for your tissues to absorb.


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Who’s affected by mouth breathing?

Mouth breathing affects adults and children. Healthcare providers estimate between 10% and 25% of children have mouth breathing.

How does mouth breathing affect people?

People who breathe through their mouth and not their nose are more likely to develop sleep disorders, including sleep apnea. Children who have mouth breathing are more likely to have dental problems like malocclusion and facial differences. They can also develop obstructive sleep apnea that healthcare providers link to learning difficulties and behavioral problems.


Is it bad to be a mouth breather?

Mouth breathing is something you do. It’s not who you are. It’s not a question of being good or bad. It’s about which way of breathing is most helpful and healthful. Breathing through your nose instead of your mouth is better on both counts.

Symptoms and Causes

What causes mouth breathing?

Mouth breathing happens when people can’t breathe through their noses. Some conditions that affect nasal breathing include:

  • Enlarged adenoids: Adenoids are glands that look like small lumps of tissue located above the roof of your mouth and behind your nose. Adenoids protect young children from bacteria and viruses. Sometimes, adenoids are swollen or infected, blocking children’s airways. Adenoids typically shrink as people age, so enlarged adenoids are less likely to cause mouth breathing in adults.
  • Nasal congestion: If you have allergies, colds or chronic sinusitis, you may have a persistent stuffy nose that keeps you from breathing through your nose.
  • Deviated septum: Your septum is cartilage and bone that divides the inside of your nose into two sides. When your septum leans to one side, it can block your airway.


What are mouth breathing symptoms?

Many mouth breathing symptoms affect children and adults the same way. Here are some examples:

  • Dry mouth: Breathing through your mouth as you sleep dries salvia that keeps your mouth moist.
  • Bad breath: Mouth breathing affects saliva flow that usually keeps your mouth clean.
  • Drool on pillows: Saliva that usually collects in your mouth seeps out from your open mouth.
  • Malocclusion:Malocclusion happens when your upper and lower teeth don’t align.

Children who mouth breath have different and more serious symptoms:

  • “Mouth breathing face”:Mouth breathing can affect children’s facial development, causing what’s called “mouth breathing face.” People who have mouth breathing face often have narrowed faces with receding chins or jaws.
  • Behavior problems:Studies show some children with mouth breathing develop behavioral problems that are similar to problems found with children who have attention deficit hyperactivity disorder (ADHD).

Diagnosis and Tests

How do healthcare providers diagnose mouth breathing?

Healthcare providers diagnose mouth breathing by doing a physical examination, checking your or your child’s adenoids, tonsils and nose for any problems that may affect the ability to breathe through your or your child’s nose. They may ask about sleeping habits, too.

What tests do healthcare providers do to diagnose mouth breathing?

Some tests healthcare providers may use include:

  • Lip seal test: This test evaluates whether you can breathe with your mouth closed.
  • Mirror test:Your healthcare provider holds a mirror under your nose looking for clouding or condensation that indicates you’re breathing through your nose.
  • Water test:This test checks your ability to hold water in your mouth.

Management and Treatment

How do healthcare providers treat mouth breathing?

Mouth breathing often happens when something blocks your nasal passages. Some children have mouth breathing because they have enlarged adenoids. Healthcare providers may recommend the following surgeries:

  • Adenoidectomy: Removing infected or swollen adenoids opens up children’s airways.
  • Septoplasty: This surgery repairs deviated septums that may cause breathing problems.

Chronic colds, sinus infections and allergies also cause mouth breathing. Healthcare providers may recommend medication to ease congestion that keeps people from breathing through their noses.


Can mouth breathing be prevented?

You can’t keep children from breathing through their mouths. But you can help your child so they don’t make mouth breathing a harmful habit. Here are some suggestions:

  • Watch for runny noses and other signs of nasal congestion. Children who have chronic nasal congestion are more likely to develop mouth breathing.
  • Check your child’s sleeping habits. If they’re restless sleepers, they snore or they mostly breathe through their mouths when they sleep, they may be developing mouth breathing.

If your child seems to be breathing through their mouth more than their nose, ask their healthcare provider to evaluate your child for mouth breathing, including physical problems that may keep them from breathing through their nose.

How can I prevent mouth breathing as an adult?

As with children, you may not be able to prevent mouth breathing, but you can get help to stop mouth breathing before it causes problems such as bad breath and restless sleep. Talk to your healthcare provider if you think you may have started breathing through your mouth as you sleep.

Outlook / Prognosis

What can I expect if I have/my child has this condition?

Many times, healthcare providers can eliminate mouth breathing symptoms by treating the underlying problem. That may mean surgery to remove tissue that’s blocking your or your child’s airway. You or your child may need medication to reduce allergic reactions like chronic stuffy noses.

A note from Cleveland Clinic

Mouth breathing is a habit people develop when they can’t breathe through their nose. Mouth breathing may solve the immediate and essential problem of getting enough air. But mouth breathing can become a hard-to-break habit that can cause sleep disorders, dental problems and facial structure differences. Talk to your healthcare provider if you think you or your child is developing mouth breathing. They’ll recommend treatments or medication to resolve the problem.

Medically Reviewed

Last reviewed on 04/11/2022.

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