Why do we drool in our sleep?

Drooling during sleep can be caused by various reasons, such as producing too much saliva, open mouth breathing, or difficulty swallowing. ^[4]

Individuals with neurological disorders may experience drooling as a side effect of their condition. ^[2] For older adults, drooling can be a sign of a neurological disorder or a side effect of some medications used to treat dementia. ^[5]

Here are a few of the most common causes of nighttime drooling: ^[6]

Sleeping position

How you sleep can affect whether or not you drool at night. “When you sleep on your side or stomach, gravity can cause saliva to pool in your mouth and leak out, leading to drooling,” says Eichelberger. ^[2]

Allergies or infections

Allergies and infections can be more than an occasional annoyance. Seasonal allergies, a cold, a sore throat, nasal congestion, sinus infections, and a stuffy nose can all cause drooling in your sleep. These conditions can inflame sinus passages and block airways, making breathing through the nose more difficult, which could lead to excessive saliva production during sleep. ^{[2, 6, 7]}

Gastroesophageal Reflux Disease (GERD)

Gastroesophageal Reflux Disease (GERD), or acid reflux, occurs when stomach acid frequently travels back into the esophagus. Some people with this condition may produce excessive saliva, leading to drooling during sleep. If you’re battling nighttime drooling and acid reflux, avoid eating large meals too close to bedtime, eat a fiber-rich diet, and consult a healthcare provider if symptoms interrupt sleep. ^{[8, 9]}

Obstructive sleep apnea

Obstructive sleep apnea (OSA) can impair your ability to breathe well during sleep. This condition forces you to breathe through your mouth, which can increase the odds of drooling during sleep. ^[7] People with sleep apnea may also grind their teeth, which also increases the likelihood of drooling during sleep. ^{[10, 11]} If you suspect you suffer from sleep apnea, it’s important to see your healthcare provider for ways to treat this condition.

Teeth grinding

Bruxism, or teeth grinding, can cause drooling during sleep. ^[11] It affects up to 10% of people and can be triggered by stress and anxiety. _^[12] Sleep apnea, certain antidepressants, and alcohol, caffeine, and tobacco use can also cause bruxism. Wearing a mandibular device at night can prevent the tongue and teeth from excessive movement, which reduces both grinding and drooling episodes.

Medication side effects

Certain medications, such as SSRIs, a type of antidepressant, can make you more likely to drool at night.^[13] Other medications that can cause excessive saliva production are antipsychotic drugs like clozapine, used to treat dementia and Alzheimer’s, and some antibiotics. _{^{[5, 7]}}

Other medical conditions

Certain medical conditions can affect the neurological system and increase saliva production. Conditions like Parkinson’s disease, cerebral palsy, and stroke are just a few that can increase the risk of drooling during the night. ^{[2, 7]}

For older adults, drooling can be caused by neurological conditions, such as a stroke or a side effect of a certain type of medication. ^[5]

Other medical conditions that contribute to difficulty swallowing and excessive drooling are: _{^{[2, 6, 7]}}

• Bell’s Palsy
• Huntington’s disease
• Amyotrophic lateral sclerosis (ALS)
• Traumatic brain injury