Drooling during sleep is usually a sign your body is deeply relaxed — but several factors can contribute.
1. Deep Sleep
During REM and deep sleep stages, muscles — including those controlling swallowing — relax. You swallow less often, so saliva can escape. This often indicates good sleep quality.
2. Sleep Position
Side or stomach sleeping makes drooling more likely because gravity pulls saliva outward. Back sleeping reduces the chance since saliva is more easily swallowed.
3. Nasal Congestion
Colds, allergies, sinus issues, or a deviated septum can cause mouth breathing, increasing drooling.
4. Excess Saliva Production
Some medications (for allergies, depression, or neurological conditions) and acid reflux (GERD) can increase saliva.
5. Neurological or Sleep Disorders
Conditions like sleep apnea, Parkinson’s disease, or stroke can affect swallowing and muscle control, leading to drooling. Sleep apnea often involves mouth breathing and disrupted sleep.
When to See a Doctor
Occasional drooling is normal. But if it’s new, excessive, or paired with symptoms like snoring, choking, or trouble swallowing, medical advice is recommended.
How to Reduce It
- Sleep on your back
- Treat nasal congestion
- Stay hydrated
- Review medications with your doctor
- Get evaluated for sleep apnea if needed
In most cases, drooling simply means your body is fully at rest — but persistent or severe symptoms shouldn’t be ignored.