Why do I drool when I sleep?
Last updated September 3, 2026.
Sleep drooling is gravity plus a relaxed, open mouth: saliva escapes instead of being swallowed. MedlinePlus frames drooling as a problem of keeping saliva in, swallowing it, or making too much, and the sleep version is almost always the first, amplified by mouth breathing from a blocked nose or allergies. Back sleeping, decongesting before bed, and staying hydrated all help. It deserves a GP mention when it is new and heavy, one-sided, paired with facial weakness or swallowing trouble, or joined by loud snoring with gasping pauses, since the NHS warns snoring can sometimes be sleep apnoea.
What to do
- Try sleeping on your back; gravity stops doing the drooling for you.
- Clear your nose before bed with saline spray or your usual allergy treatment.
- Stay hydrated; thick saliva drools worse.
- See a GP for new heavy drooling, one-sided drooling, swallowing trouble, or snoring with gasping pauses.
Related questions
- Why do I get a dry mouth at night?
- What are the signs of sleep apnea?
- Why do I get a sore throat from sleeping with my mouth open?
- Why do I feel tired after 8 hours of sleep?
