Have you ever woken up to find drool on your pillow? Drooling occurs when saliva involuntarily flows out of your mouth. It’s common in infants and toddlers, who can’t yet fully control the muscles around their mouths. And adults may drool in their sleep due to factors like diet, sleep position, or medication side effects.
“A little drooling during sleep is common and usually not something people need to worry about,” says Davud Sirjani, MD, an otolaryngologist at Stanford Medicine in Palo Alto, California.
But if you notice new or excessive drooling, or if it is associated with symptoms such as difficulty swallowing, loud snoring, daytime fatigue, or certain neurological conditions like Parkinson’s disease, it may signal an underlying medical condition.
Here are some common causes of nighttime drooling and when to see a doctor.
1. Sleep Position
Try sleeping on your back instead. If that’s challenging, you can use pillows to prop yourself up and keep yourself from rolling over at night.
2. Sleeping With Your Mouth Open
Another common cause is sleeping with your mouth open. “Often, people are not producing too much saliva — they’re simply sleeping with their mouth open,” Dr. Sirjani says. Mouth breathing — or frequently breathing through your mouth rather than your nose — can result from issues like nasal congestion, a deviated septum, or sleep apnea (more on these below).
You may be able to address mouth breathing by using nasal strips or decongestants or antihistamines to treat congestion or allergies. But mouth breathing can be a symptom of a more serious condition, so it’s important to see your doctor if it doesn’t go away or is accompanied by other symptoms, such as headaches, daytime fatigue, or mood changes.
3. Obstructions in Your Nose or Throat
Physical blockages in the nose or throat can cause nighttime drooling. “In kids, big adenoids or tonsils often force mouth breathing,” says Tochi Iroku-Malize, MD, MPH, a family medicine physician at Northwell Health in New Hyde Park, New York. The adenoids are glands located in the upper airway that help fight off germs and bacteria. In children, they can swell, causing breathing issues, but they often shrink and disappear by adulthood.
In adults, a deviated septum, enlarged turbinates (small bony structures in the nose that clean and humidify air), or nasal polyps (noncancerous growths in the nose) can do the same.
If you think you may have an obstruction, talk to your doctor. They’ll examine your nose and throat and recommend an appropriate treatment, such as:
Removal of enlarged tonsils (tonsillectomy) or adenoids (adenoidectomy)
Correction of a deviated septum (septoplasty)
Removal of nasal polyps
Reduction of the nasal turbinates (turbinectomy or turbinoplasty)
4. Congestion
Seasonal allergies or viral infections like the common cold can cause congestion, making breathing through the nose difficult. “Once the nose becomes blocked, people start breathing through their mouth, especially while asleep,” Sirjani says.
5. Dental Issues
Misaligned teeth, poorly fitted dentures, or an open bite (a condition in which the upper and lower teeth don’t touch when your mouth is closed) can contribute to nighttime drooling, says Louis Siegelman, DDS, a dentist in New York City. “The loss of structural support from the teeth and jawbone can change the seal around the lips and potentially lead to drooling,” he says.
Any foreign objects, such as mouth guards, nighttime snoring appliances, orthodontic devices, and tongue or lip piercings, can also contribute to nighttime drooling, Dr. Siegelman says. It’s best to see a dentist, who can determine the cause and the best way to cope. For example, they may suggest refitting dentures or using braces or clear aligners to correct misaligned teeth.
6. Sleep Apnea
Sleep apnea is a sleep disorder that causes breathing pauses during sleep, which may lead to nighttime drooling. “If someone has excessive drooling along with loud snoring, witnessed pauses in breathing, or significant daytime sleepiness, sleep apnea should be considered,” Sirjani says.
These are the main types of sleep apnea:
Obstructive sleep apnea (OSA) is a condition in which the muscles in the back of the throat relax too much during sleep, temporarily blocking the airway and causing pauses in breathing.
Central sleep apnea (CSA) occurs when the brain doesn’t send proper signals to the muscles that control breathing, resulting in short pauses in breathing.
Complex sleep apnea, which occurs when OSA changes to CSA during sleep apnea treatment.
OSA can be treated with a continuous positive airway pressure (CPAP) machine, which keeps your airway open. If you find the CPAP uncomfortable or have only mild to moderate sleep apnea, an oral appliance can help keep your jaw or tongue in the right position. Oral appliances can also increase salivation, though, leading to drooling.
Lifestyle changes — such as sleeping on your side, quitting smoking, avoiding alcohol and sedative medications later in the day, and exercising regularly — may also help alleviate symptoms. Talk to your doctor if you have (or suspect you have) sleep apnea. They can help you determine the best way to cope based on factors such as your specific condition and any co-occurring health issues.
7. Gastroesophageal Reflux Disease (GERD)
Gastroesophageal reflux disease (GERD) can cause water brash, a condition in which increased stomach acid production causes you to produce more saliva to help wash the acid back down. “Left untreated, GERD can increase salivary production during the nighttime,” says Hunter McLaughlin, DO, an internal medicine specialist at Wilmington Health in Wilmington, North Carolina.
You can reduce GERD-related nighttime drooling by avoiding GERD attacks. Some ways to do this include limiting or avoiding trigger foods like alcohol, caffeine, or spicy foods; eating smaller, more frequent meals; staying upright for at least two hours after eating; and elevating your head for sleep. Your doctor may also recommend over-the-counter or prescription medications to help neutralize existing stomach acid, prevent or reduce acid production, and heal the esophagus.
8. Certain Neurological Conditions
Swallowing requires your brain and throat muscles to coordinate. Certain neurological conditions can interfere with that process, leading to excess saliva and drooling. These conditions include:
Keeping drooling under control isn’t just about comfort for patients with neurological conditions; it’s essential for their safety and quality of life. “These cases sometimes carry a high risk of saliva being inhaled into the lungs (aspirated), so they need specialist care — speech therapy, swallowing therapy, and sometimes medical or surgical treatments,” Iroku-Malize says.
If you have been diagnosed with one of these conditions and experience nighttime drooling, speak with your doctor about treatment options. If you’re experiencing new neurological symptoms — such as difficulty swallowing, weakness of the muscles around your mouth, or coughing or choking while eating, drinking, or sleeping — along with nighttime drooling, discuss your concerns with your primary care doctor. They can refer you to a specialist to investigate the possible causes.
9. Medication Side Effects
Some psychiatric medications, such as clozapine for schizophrenia, can cause drooling as a side effect. Additionally, some drugs used to treat Alzheimer’s disease, myasthenia gravis, and other neurological conditions can cause drooling.
If nighttime drooling begins after you start a new medication, discuss it with your doctor. “A careful review of a patient’s medications is important, but so is a thorough history looking for other explanations that may be contributing to the problem,” says Sirjani.
10. Other Health Conditions
Other conditions that may cause nighttime drooling include:
Bell’s palsy from facial nerve inflammation
Epiglottitis, a medical emergency in which the epiglottis (the cartilage that covers the windpipe) swells, blocking the airway
Wilson disease, a rare genetic disorder that causes copper to accumulate in the body and leads to drooling due to facial stiffness (dystonia) and swallowing difficulties (dysphagia)
Although nighttime drooling is typically harmless, if it doesn’t go away, worsens, affects your sleep quality, causes skin irritation, or is accompanied by other symptoms, it’s time to see a doctor, Sirjani says. “A new change in drooling, particularly in an adult, should not be ignored.”
If your drooling occurs suddenly alongside difficulty breathing, trouble swallowing, a severe sore throat, hoarse or quiet voice, and stridor (a high-pitched sound when breathing in), this may signal epiglottitis, a life-threatening emergency. In this case, call 911 or head to the emergency room immediately.
