why spitting while sleeping?

Everyday I find that I always spit while I was sleeping. The evident is that I have seen the spit on my pillow :( Could u do me a favor? I'd like to get the solution to eliminate this kind of bad behavior. Thanks

[Dr Santos]

Hi,
How are you? Are there other symptoms present? Do you have history of reflux or oral lesions? Saliva is usually produced in and secreted from salivary glands containing water, electrolytes, mucus and enzymes.Excessive salivation is a symptom of almost any lesion in the oral cavity and this may be one reason why there is spitting while sleeping. You may need to have this checked by your doctor for proper evaluation. Take care and regards.