If you have a partner who drools in their sleep, this article may finally explain why. And if someone has just sent this to you, do not worry — night-time drooling is far more common than you think. Here is what causes it, what is normal, and when it is worth paying attention.
Waking up to a damp pillow is not the nicest way to start the day. It can feel embarrassing and uncomfortable, especially if it begins happening more often than before. The good news: once you understand why drooling occurs, there are practical steps you can take to reduce it and recognise when it may indicate something more.
This guide explains why drooling during sleep happens, what is considered normal, what you can do about it, and when to speak with a healthcare professional.
Is It Normal to Drool in Your Sleep?
In most cases, yes. Occasional drooling during sleep is usually normal.
Your salivary glands continue to produce saliva throughout the night to keep the mouth and throat moist. At night, saliva production tends to decrease, but does not stop completely. If your swallow reflex is reduced or your mouth is slightly open, saliva can pool and leak out as drool.
For many people, this is simply a minor inconvenience. However, very heavy, frequent, new, or persistent drooling may warrant a closer look, especially when accompanied by symptoms such as breathing difficulty, disturbed sleep, facial pain, or trouble swallowing.
Common Causes of Drooling at Night
1. Sleeping Position
Sleeping on your side or stomach allows gravity to pull saliva out of the mouth.
Back sleeping keeps the mouth more naturally closed, helping saliva drain toward the throat instead of the pillow.
People who mouth-breathe during sleep are especially likely to drool in these positions.
2. Nasal Congestion and Allergies
Blocked nasal passages force you to breathe through your mouth. This can happen during:
- Colds
- Sinus infections
- Allergies
- Pregnancy-related nasal congestion
When your nose is congested, mouth breathing becomes the default, and drooling increases.
3. Gastroesophageal Reflux Disease (GERD)
GERD can irritate the throat and make swallowing uncomfortable. The body may respond by producing extra saliva to soothe the irritation.
Difficulty swallowing (dysphagia) is also common with GERD, and both can lead to drooling at night.
4. Obstructive Sleep Apnoea (OSA)
OSA causes repeated pauses in breathing during sleep. Many people with OSA breathe through their mouth or sleep with their mouth open, increasing drooling.
Other signs of OSA include:
- Loud snoring
- Gasping or choking during sleep
- Daytime sleepiness
- Morning headaches
If drooling occurs alongside these symptoms, an evaluation for sleep apnoea is recommended.
5. Bruxism (Teeth Grinding)
Night-time teeth grinding is associated with mouth breathing and jaw tension. Both can make it harder to keep saliva inside the mouth. Wearing a night guard can also increase salivation temporarily.
6. Oral Health Problems
Saliva can increase when the mouth is irritated or inflamed. You might drool more at night if you have:
- Cavities
- Gum disease
- Mouth ulcers
- Oral infections
If drooling appears suddenly with mouth pain or swelling, a dental check is advised.
7. Medications
Some medications stimulate saliva production or interfere with swallowing. These include:
- Certain antibiotics
- Antipsychotic medications
- Alzheimer’s medications
- Some sedatives
If drooling began after starting a new medication, speak with your doctor about alternatives.
8. Neurological Conditions
Conditions that affect muscle control or swallowing can cause hypersalivation. Examples include:
- Parkinson’s disease
- Stroke
- Cerebral palsy
- Amyotrophic lateral sclerosis (ALS)
- Bell’s palsy
These are less common causes, but drooling may be more persistent and occur during daytime as well.
Can Night-time Drooling Cause Problems?
For most people, drooling during sleep is more of an annoyance than a danger. However, heavy or persistent drooling can:
- Disturb sleep and lead to daytime fatigue
- Irritate the skin around the mouth and chin
- Cause bad breath
- Contribute to mild dehydration if severe
When drooling occurs alongside acid reflux, there may also be a risk of long-term damage to teeth and the lining of the mouth from stomach acid. In rare severe cases, very heavy salivation can increase the risk of coughing or choking, particularly in people with swallowing difficulties.
How to Reduce Drooling in Your Sleep
The best approach depends on the underlying cause. In many cases, simple changes can reduce drooling significantly.
Adjust Your Sleeping Position
If you mostly drool when sleeping on your side or stomach, try:
- Switching to sleeping on your back
- Using a flatter pillow if you move from side to back sleeping
- Placing pillows beside your body to make it easier to remain on your back
Raising the head of the bed slightly or using a wedge pillow can also help saliva move towards the throat for swallowing rather than out of the mouth.
Improve Nasal Breathing
If congestion is a recurring problem, focus on keeping your nose as clear as possible:
- Treat colds, flu, or sinus infections as advised by your healthcare provider
- Consider saline nasal sprays or irrigation to gently clear mucus
- Discuss antihistamines or other allergy treatment if you have allergic rhinitis
- Use a humidifier if the air in your room is very dry
Better nasal airflow makes mouth breathing less likely and may directly reduce drooling.
Read also: How to Sleep With a Blocked Nose
Look After Oral and Dental Health
If you have signs of gum disease, tooth decay, or mouth sores, schedule a dental review. Treating underlying oral issues helps reduce irritation that may be triggering extra saliva.
If you grind your teeth, your dentist or doctor may suggest a night guard or other device. This may initially increase saliva but can protect your teeth and improve sleep quality in the long term.
Address Underlying Medical Conditions
If drooling is linked to GERD, sleep apnoea, or a neurological condition, managing that condition is essential. Depending on the diagnosis, treatment might involve:
- Medication and lifestyle changes for reflux
- CPAP or oral devices for sleep apnoea
- Medications and rehabilitation strategies for neurological conditions
Your doctor may also refer you to a speech or swallowing therapist. Targeted exercises can strengthen the muscles around the mouth and throat and improve control of saliva and swallowing.
Medical Treatments for Excessive Drooling
For more severe or persistent drooling, especially in people who drool during the day as well, additional medical options may be considered:
- Botulinum toxin injections into the salivary glands to reduce saliva production temporarily
- Medications that reduce salivary gland activity (often used in neurological conditions, but they may cause a dry mouth and other side effects)
- Surgery on the salivary glands or ducts in very severe cases that do not respond to other treatments
These approaches are usually reserved for people whose drooling significantly affects comfort, social confidence, or daily care.
When Should You See a Healthcare Professional?
Occasional drooling during sleep is usually harmless. However, you should seek medical advice if you notice:
- A sudden or marked increase in drooling
- Difficulty breathing or swallowing
- Loud snoring, gasping, or pauses in breathing during sleep
- Extreme tiredness or sleepiness during the day
- Mouth or facial pain, swelling, or signs of infection
- Tooth or gum pain, tooth sensitivity, or changes in your bite
- Drooling that begins after starting a new medication
- Other neurological symptoms such as weakness, facial droop, or trouble speaking
A healthcare provider can assess whether your drooling is simply a normal variation, or a sign of something that needs further attention and treatment.
Key Takeaway
Drooling during sleep is common and often linked to how you sleep, how easily you can breathe through your nose, and how relaxed your mouth muscles are during deep sleep.
If it is mild and occasional, it is usually nothing to worry about. However, if drooling is heavy, frequent, new, or accompanied by other symptoms such as breathing, swallowing, dental, or neurological problems, it is worth discussing with a healthcare provider.
With the right combination of sleep habit changes, medical assessment when needed, and targeted treatment for underlying conditions, most people can reduce night-time drooling and wake up feeling more comfortable and well rested.
External References
- A.D.A.M. Medical Encyclopedia. (2019, September 16). Drooling. MedlinePlus. https://medlineplus.gov/ency/article/003048.htm
- MedlinePlus: National Library of Medicine (US). (2016, August 31). Swallowing disorders. https://medlineplus.gov/swallowingdisorders.html
- Bavikatte, G., Sit, P. L., & Hassoon, A. (2012). Management of drooling of saliva. British Journal of Medical Practitioners, 5(1), a507. https://www.bjmp.org/content/management-drooling-saliva
- Spicuzza, L., Caruso, D., & Di Maria, G. (2015). Obstructive sleep apnoea syndrome and its management. Therapeutic Advances in Chronic Disease, 6(5), 273–285. https://pubmed.ncbi.nlm.nih.gov/26336596/
- Lakraj, A. A., Moghimi, N., & Jabbari, B. (2013). Sialorrhea: Anatomy, pathophysiology and treatment with emphasis on the role of botulinum toxins. Toxins, 5(5), 1010–1031. https://pubmed.ncbi.nlm.nih.gov/23698357/
