If you’ve ever had dry mouth at night, you’ve probably woken up with classic signs of cottonmouth, including a dry, sticky mouth that makes you want to reach for a glass of water. Understanding what causes dry mouth at night can help you address side effects, such as bad breath, a higher risk of cavities, gingivitis, or irritation underneath your dentures. Keep reading to dig into some of the most common symptoms and causes of dry mouth during sleep and discover some solutions.
What Causes Nighttime Dry Mouth?
It’s normal for your saliva glands to reduce saliva production while you sleep. Since we’re not eating, drinking, or talking while we sleep, the saliva glands don’t need to function the same way they do when we’re awake. However, approximately 1 in 4 people experience persistent, more severe dry mouth, or xerostomia.
Many factors can reduce saliva production, causing oral dryness at night. For example, sleeping with your mouth open, using a CPAP machine, sinus blockage, or even the medications you take right before bed may contribute to dry mouth.
One of the most common side effects of medications — specifically decongestants, antihistamines, and antidepressant drugs — is dry mouth. If you take these medications right before going to bed at night, your mouth may be extremely dry the next morning. In fact, xerostomia (dry mouth) is one of the most common effects of prescription and over-the-counter drugs, and at least 400 different medications can cause it, according to the Washington Dental Hygienists’ Association.
While you may not want to discontinue medication because of dry mouth symptoms, speak with your physician about the time of day you take it, especially if you’re trying to figure out how to prevent dry mouth while sleeping.
To prevent dry mouth while sleeping, assess your nighttime breathing style. If possible, ask for the help of a family member or roommate. Do you tend to sleep with your mouth closed or open? Do you snore? Ask someone you trust to check on you during the night to find out how your mouth is positioned and if you’re breathing through it rather than your nose.
Similarly, check yourself for daytime mouth breathing. When your mouth rests, your lips should be closed. But if your lips are open and you breathe in through your mouth during the day, this habit can amplify dry mouth at night. Mouth breathing is common for people with allergies and nasal blockage.
Exercise is a classic example of where breathing styles are important. For competitive athletes who do most of their breathing through their mouths during training, this practice can further dry out their oral tissues. Many athletic trainers recommend controlling oxygen intake by breathing in through the nose and out through the mouth during workouts rather than breathing solely through the mouth during their activity.
Studies show that people who use continuous positive airway pressure (CPAP) therapy for sleep apnea have a 57 percent chance of having dry mouth upon waking compared to a 17 percent chance for those who do not use a CPAP machine. Because these devices mechanically force air into your lungs, it’s common to see people sleep with their mouths open. How do you avoid dry mouth while sleeping with a CPAP? A moisturizing mouth rinse that lubricates your oral tissues before going to sleep will help.
You may also want to work with your physician to modify your breathing style if you’re a mouth breather. However, surprisingly, many people who use a CPAP experience dry mouth even when their mouths are closed with tape or a chin strap. Researchers think pressure against the saliva glands created by the CPAP appliance may cause the issue.
Persistent seasonal allergies and sinus congestion can make it difficult, if not impossible, to breathe through your nose. One of the most common causes of dry mouth when sleeping is due to inflammation and blockage in our nasal sinuses. When you lay your head on your pillow at night, the sinus pressure may feel worse than when your head’s elevated.
Everyone has a thin tissue that serves as a wall between their nasal passages, called a septum. A deviated septum happens when this wall is offset, partially blocking one of the nasal passages and making it smaller than the other. About 75 to 80 percent of people have some degree of septal deviation. People with a severely deviated septum may be more likely to experience dry mouth while sleeping because of mouth breathing due to restricted nasal airflow.
Wearing a removable appliance such as a denture, partial, orthodontic retainer, or similar device may cause dry mouth. For example, while the research is limited, many orthodontists warn that braces and invisible aligners may cause dry mouth. They explain that these treatments can cause irritation, and your body may respond by reducing saliva production.
Moreover, dental devices can be extremely uncomfortable if you have a dry mouth. Additionally, a dry mouth environment can predispose you to chafing or sores due to the lack of a natural lubricant between your mucosal tissues and dental prosthesis. If you have an irritated, dry mouth when sleeping, using an aloe-vera-based product can provide noticeable relief of dry mouth symptoms in addition to products designed to soothe dry mouth. Note that dentists and dental specialists advise against sleeping in a removable denture or partial prosthesis.
Symptoms of Dry Mouth During Sleep
Aside from a dry, sticky mouth in the morning, people who breathe through their mouths while they sleep also tend to experience classic signs of morning breath. While waking up with bad breath doesn’t inherently mean you have a problem with your breathing, mouth breathing can amplify bad breath because it dries out the oral mucosal tissues. When we have dry mouth while sleeping, certain types of bacteria can thrive in an environment that allows for odorous sulfur-causing byproducts.
Other symptoms of a dry mouth at night can include a scratchy, irritated throat that may mirror the symptoms of seasonal allergies, a rough tongue, and cracked lips.
To treat dry mouth when sleeping, it’s helpful to focus on a preventative approach throughout the day. You also may want to change your bedtime routine. After all, it’s not feasible or reasonable to physically wake yourself up throughout the night to sip on water or to make sure you’re breathing through your nose. Fortunately, lifestyle changes and over-the-counter products can help you lubricate your mouth and lessen saliva loss to keep your mouth more comfortable at night (and reduce the chances you’ll experience morning breath).
Lifestyle changes for minor dry mouth
What are some changes you can make in your daily routine to minimize dry mouth at night?
- Eliminate alcohol intake late in the evening.
- Reduce your caffeine
- Cut out tobacco products or similar vaping agents.
- Drink more water throughout the daytime.
- Use a humidifier.
- Practice breathing through your nose and not your mouth
- Do not sleep in dentures or partials.
- Take medications earlier in the day, as directed by your physician.
- Address issues like sinusitis, allergies, or sleep apnea that cause you to breathe through your mouth.
Products that may provide relief
While oral care products that contain alcohol may dry out your oral cavity, some products without alcohol provide added moisture and lubrication to prevent dry mouth. Sugar-free mints designed for dry mouth can stimulate saliva production and help create a thin barrier over the skin. Mouthwash that contains zinc ions and other ingredients used to combat oral dryness can be helpful if you use it before bed.
When to See Your Dentist
Most people should schedule a preventative-care appointment with a dentist every six months. During these visits, communicate with your dental team about symptoms like persistent dry mouth.
Your dental providers can help counteract tooth demineralization triggered by xerostomia. They may apply fluoride or recommend a modified oral hygiene technique. While you’re there, share a list of all prescription and over-the-counter medications you take, so your dentist can provide input on how they may affect your dry mouth symptoms.
Having a mildly dry mouth when sleeping isn’t always a bad thing. After all, it’s natural for saliva glands to decrease their production while we sleep. But if your mouth is severely dry, it can cause discomfort, increase your risk of tooth decay, and even make your breath smell worse in the morning. Using the right moisturizing oral health products and adjusting your nighttime routine is key to protecting your oral health. Also, be sure to plan regular checkups with your dentist to screen for effects of dry mouth, such as enamel demineralization and tooth decay.