Sleeping With Your Mouth Open: What It Means and When It Matters

Have you woken up in the morning feeling less refreshed than you’d expect? Perhaps you’re experiencing daytime fatigue, a dry mouth, or a sore throat — nothing super serious, but enough to notice something’s off. Maybe your partner recently mentioned that you’ve been sleeping with your mouth open. Could there be a connection? 

While mouth breathing while sleeping seems pretty harmless, it is often a sign of the body compensating for something, like nasal obstruction, or possibly sleep-disordered breathing like sleep apnea. So if you think you’re sleeping with your mouth open, or you’ve noticed that your partner is doing so, it’s worth investigating further. 

In this article, we’ll examine the different reasons why you or your partner may be sleeping with your mouth open, as well as what can happen if mouth breathing remains unaddressed. We’ll also discuss potential solutions and when mouth breathing warrants a conversation with your medical provider.

Why do people sleep with their mouth open?

While there are several different causes of sleeping with your mouth open, nasal air obstruction is usually the reason, per research in JAMA Otolaryngology-Head & Neck Surgery.

“[Mouth breathing] almost always comes back to one thing,” observes Luke Bauserman, DDS, D.ABDSM, CCSH, Director, Better Sleep Mid-Ohio Valley: Center for TMJ & Sleep Apnea. “The person can't move enough air through the nose, so the body defaults to the mouth.”

Dr. Bauserman explains four common causes of mouth breathing while sleeping:

Nasal obstruction and congestion

There can be either temporary causes of mouth breathing, like a cold, allergies, or a sinus flare, or chronic, structural causes like a deviated septum and/or enlarged turbinates. 

A deviated septum occurs when the cartilage and bone that separates your nasal cavity is off-center. This can be a congenital condition or caused by a nose injury.

Turbinates are small structures in the nose that cleanse and humidify air that passes through the nostrils into the lungs. They can become enlarged or swollen due to allergies, irritation, or infection, thus leading to nasal obstruction and congestion — and nocturnal mouth breathing.

“Patients with a high, narrow palate very often have a deviated septum, and they’ll often tell you they breathe fine through one side of the nose but barely at all through the other,” says Dr. Bauserman. “If you can't breathe through your nose, you're going to mouth-breathe.”

For people with a deviated septum and/or enlarged turbinates, there are effective, outpatient procedures like septoplasty (to correct a deviated septum) and turbinate reduction (to open blocked nasal passageways) available, which “can genuinely change someone’s sleep,” says Dr. Bauserman. 

Enlarged tonsils or adenoids

The tonsils are pads of tissue located on each side of the back of the throat, while adenoids are similar pads of tissue that sit right behind the nose. Both are responsible for initiating immune responses against germs entering the body. 

But when the tonsils and/or adenoids are enlarged, they can cause mouth breathing in children because they physically block nasal airflow. They are also the most common cause of pediatric obstructive sleep apnea, which affects 1-5% of children globally, according to a 2024 study in Cureus. 

If your child exhibits loud snoring, gasping or choking sounds during sleep, restless sleep, or daytime sleepiness, it may be time for a doctor’s evaluation. First-line treatment often involves the removal of enlarged tonsils/adenoids. 

Sleep-disordered breathing 

Mouth breathing can be a sign of sleep apnea or upper airway resistance, but nasal breathing problems and throat-level obstruction “often reinforce each other,” says Dr. Bauserman, so it’s important to understand how they’re connected. 

“When the airway is narrow and prone to collapse, the person is fighting to move air, and the mouth opens as part of that struggle,” explains Dr. Bauserman. “A restricted nasal airway increases the negative pressure in the throat during inhalation, which makes the collapsible part of the airway more likely to obstruct.”

Sleep position and habit

Your sleeping position does ultimately matter as well. If you sleep on your back, your tongue and soft tissues may fall backward, narrowing your airway and opening your mouth, per research in Sleep. 

Sleeping habits can also directly affect mouth breathing, observes Dr. Bauserman: “Some people have [breathed out of their mouth] for so long that the pattern persists even after the nose is clear, which is why ‘retraining' is part of some treatments.”

How do you know if you're sleeping with your mouth open?

The good news is there are several ways to check for signs of mouth breathing at night, whether you’re a solo sleeper or have a bed partner who can offer their own observations. Below, Dr. Bauserman offers some clues into potential nocturnal mouth breathing:

Signs a bed partner might notice

“A partner is often the best sensor you have,” notes Dr. Bauserman. They can keep an eye out for any critical symptoms, such as if you’re sleeping with your mouth hanging open, snoring, and any gasping, choking, or pauses in breathing (which can be signs of sleep apnea). 

How to check yourself for nighttime mouth breathing

Dr. Bauserman shares the following signs that indicate you might be sleeping with your mouth open:

1. In the morning, notice if: 

• • You wake up with a dry mouth, a scratchy or sore throat, and/or bad breath. 

  • You feel tired even after a full night’s sleep. 

2. Test your nasal breathing during the day:

Try holding your lips closed for a few minutes while sitting up. If you can breathe comfortably through your nose, that’s a good sign. But if you immediately feel like you're suffocating, that’s a signal that your nose is the problem. 

3. Record yourself overnight: 

Recording yourself with a tool like the SnoreLab phone app offers deep insights into your sleeping habits, positions, and which factors may impact your nighttime breathing. All of these factors can help you build a more detailed sleep profile.

What does sleeping with your mouth open do to your body?

Sleeping with your mouth open can have a cumulative effect on your overall health. First, it can potentially cause significant oral damage, as well as affect your sleep quality. That poor sleep quality, if left unaddressed, could then lead to cardiovascular issues. 

Oral health effects

Dr. Bauserman observes that this is where dentists first see the damage of sleeping with your mouth open: Chronic dry mouth is associated with cavities, gum (periodontal) disease, and bad breath. “Mouth breathing dries out the mouth by reducing the protective flow of saliva, and saliva is your natural defense against decay and gum disease,” he explains. 

He also mentions that there's a documented association between periodontal disease and sleep apnea, “so gum problems can be a flag for something bigger going on at night.”

Sleep quality and daytime fatigue

If you’re noticing a decline in your sleep quality and an uptick in your daytime fatigue, then you may be sleeping with your mouth open. “Mouth breathing usually travels with fragmented, non-restorative sleep,” notes Dr. Bauserman. 

When you don’t get a good night’s sleep due to breathing disruptions, it can present the next day as daytime fatigue, brain fog, and low energy. These are not only “the downstream effects of a brain that keeps having to interrupt sleep to protect the airway,” says Dr. Bauserman, but they could also be signals of sleep apnea. 

When left untreated, sleep apnea can increase the risk of cardiovascular disease, including heart failure, stroke, atrial fibrillation, and hypertension.

The nitric oxide advantage of nasal breathing

A distinctive advantage of nasal breathing over mouth breathing is nitric oxide production. Per research in Acta Physiologica, nitric oxide is a gaseous molecule that plays a critical role in oxygen uptake in the lungs and vasodilation (the widening of blood vessels to enhance blood flow).

“When you breathe through your nose, air passes the nasal passages and paranasal sinuses, which produce nitric oxide,” explains Dr. Bauserman. “Nasal breathing carries that nitric oxide down into the lungs with each breath; mouth breathing bypasses the whole system, so you lose that benefit.”

Is sleeping with your mouth open a sign of sleep apnea?

Sleeping with your mouth open can be a sign of sleep apnea, which is why it shouldn’t be dismissed as a minor issue. However, mouth breathing while sleeping is not necessarily proof of sleep apnea. 

“Plenty of people mouth-breathe simply because they have a stuffy nose or a deviated septum and have perfectly normal breathing otherwise,” says Dr. Bauserman. Still, “if you drew a Venn diagram of nighttime breathing problems, sleep apnea would sit in the middle of almost all of them,” Dr. Bauserman explains. “So someone who sleeps with their mouth open is more likely to have a breathing problem.”

If you or your bed partner are noticing that, on top of mouth breathing, you’re exhibiting symptoms like snoring with your mouth open, gasping, pauses in breathing, poor sleep, or daytime fatigue, you may want to consider sleep apnea testing. 

“The only way to actually know [if you have sleep apnea] is a sleep study,” says Dr. Bauserman, Dreem Health’s at-home sleep study can provide a concrete diagnosis from your own bed, allowing you to move forward with a tailor-made treatment plan once those much-needed answers are in hand.

What can you do about sleeping with your mouth open?

The available solutions for keeping the mouth closed while sleeping range from symptom management to addressing potential airway disorders. So the more you understand what’s driving your nocturnal mouth breathing, the easier it will be to create the right kind of treatment plan. 

Address nasal congestion

If you’re trying to stop mouth breathing, this is usually the first step. Accessible options like over-the-counter nasal strips and saline rinses, or allergy management (allergy shots, sublingual immunotherapy, or medication), “open the nasal airway so the person can breathe through the nose again,” explains Dr. Bauserman. Side sleeping is also an easy, DIY option to help reduce nasal congestion throughout the night. 

While decongestant sprays like Afrin are also an option, Dr. Bauserman cautions against using them in the long term: “They cause rebound congestion if used more than a few days.” 

If sleep apnea is indeed present, however, clearing the nose won’t treat this underlying condition. “It just removes one contributor,” says Dr. Bauserman. 

Chin straps and oral devices

Chin straps are marketed as “anti-snoring” devices because they are intended to help you sleep with your mouth closed. But they’re a “limited tool,” says Dr. Bauserman, because while they do address an open mouth while sleeping, chin straps don’t address the airway collapse behind mouth breathing. Plus, he says the evidence of chin-strap efficacy, especially regarding sleep apnea treatment, is “thin.” 

Oral appliance therapy, aka mandibular advancement devices, on the other hand, “[does] something more substantive,” says Dr. Bauserman. Instead of just keeping the mouth closed (which is what a chin strap does), these devices are worn in the mouth during sleep to “hold the lower jaw forward to open the airway at the throat.”

Oral appliances are “well-supported for mild-to-moderate sleep apnea,” notes Dr. Bauserman, as well as for people who can’t tolerate CPAP therapy. 

If an oral appliance is something you’re considering, Dr. Bauserman recommends obtaining a custom-fitted one from a dental practitioner instead of purchasing an at-home impression kit or an off-the-shelf version: “A poorly made or ill-fitting oral appliance can be ineffective and carry some real dental side effects over time.”

Mouth taping — with important caveats

Mouth taping is a viral wellness trend made popular by celebrities like Jimmy Fallon and Gwyneth Paltrow. The most important thing to know before exploring this option is that you should not try it on your own if you have suspected sleep apnea, nasal obstruction, or breathing difficulty. If you have sleep apnea or another breathing problem, talk with your healthcare provider first.

“Experts have warned about the trend,” confirms Dr. Bauserman, noting that mouth taping does not treat the underlying cause of sleep apnea. 

Mouth taping is exactly what it sounds like: The act of taping the lips together at night to keep the mouth closed and to force nasal breathing. “It works best for people who can already breathe well through their nose and are dealing with a [mouth-breathing] habit rather than an obstruction,” says Dr. Bauserman of mouth taping’s benefits. “It’s a habit tool, not a medical treatment.”

Myofunctional therapy

Myofunctional therapy consists of exercises for the tongue and airway muscles to support nasal breathing. Specifically, this type of therapy targets Orofacial Myofunctional Disorders (OMDs), which are face and mouth habits or movements that can make it harder to breathe (especially through the nose), talk, or eat comfortably. 

“This is essentially strength training for the airway, on the logic that these muscles get ‘floppier’ with age like any others,” explains Dr. Bauserman. To be clear, since myofunctional therapy primarily addresses OMDs, Dr. Bauserman does not recommend it as a “standalone cure” for sleep apnea. He does, however, consider it to be a “strong adjunct” alongside treatments like oral appliances and/or CPAP therapy. 

Myofunctional therapy can be beneficial not only for adults, but children as well. A 2015 study published in Sleep found myofunctional therapy reduced the apnea-hypopnea index (a measurement of how many breath interruptions occur during sleep) by roughly 50% in adults and 62% in children. It also improved snoring, oxygen levels, and daytime sleepiness. 

Mouth breathing during sleep: approaches at a glance

These approaches vary in evidence base and appropriateness: The solution that ultimately works will depend on the underlying cause.

When should you talk to a doctor about mouth breathing during sleep?

If you (or your partner’s) mouth breathing is paired with witnessed pauses in breathing, gasping, or choking during sleep, that’s a major red flag.

Other signals that warrant medical intervention include:

• Loud, habitual snoring (“especially with the mouth open,” says Dr. Bauserman)

• Morning headaches, and a chronically dry mouth or sore throat upon waking 

• Excessive daytime sleepiness or fatigue, which can include “nodding off during the day, needing caffeine to function, or feeling unrefreshed no matter how long you sleep,” notes Dr. Bauserman.

If any of these red flags are present, the recommended next step is a sleep evaluation, which can be done at home. Dreem Health’s at-home sleep study offers a no-referral virtual consultation as well as a full sleep evaluation from the comfort of your own bed. 

The bottom line

Sleeping with your mouth open may be the sign of something relatively harmless (the common cold or allergies), or it could signal something much more serious (sleep apnea). 

Even if you feel like you might be overreacting, it’s always better to err on the side of caution when it comes to your nighttime breathing habits. Scheduling a home sleep test with Dreem Health is an easy way to find out more. Once you understand the root cause of your mouth breathing, whether it’s through a doctor’s visit or an at-home sleep evaluation, the sooner you’ll wake up refreshed. 

Frequently asked questions (FAQs) 

Why does my partner sleep with their mouth open?

Nasal air obstruction is why your partner sleeps with their mouth open. When someone can’t move enough air through the nose, the body will default to the mouth. The causes of nasal air obstruction vary, and range in severity: from congestion to a deviated septum, to common enlarged tonsils/adenoids, to obstructive sleep apnea.

Is sleeping with your mouth open bad for you?

Think of sleeping with your mouth open as a potential warning signal. It’s not a diagnosis, but it’s a starting point for a conversation with your healthcare provider, especially if you’re exhibiting additional symptoms that point to sleep apnea.

Is mouth taping safe?

Mouth taping is not safe for anyone with suspected sleep apnea, nasal obstruction, or any breathing difficulty. This wellness trend, which consists of taping the mouth shut while sleeping, works primarily for people who are trying to break a mouth-breathing habit, not fix an underlying medical issue. 

Does sleeping on your side help with mouth breathing?

Yes, sleeping on your side can help with mouth breathing because it prevents the tongue and soft tissues from falling backward. This typically keeps your airway from narrowing and your mouth from opening. But sleeping on your side does not treat underlying issues like sleep apnea.

Is mouth breathing during sleep always a sign of something serious?

No, mouth breathing during sleep isn’t always a sign of something serious. But since it can suggest serious medical issues like sleep apnea, it’s a signal you don’t want to ignore, especially if you’re a loud snorer and also experience excessive daytime fatigue.