As the production of saliva increases, the accumulation of saliva is caused by a decreased swallowing reflex combined with an impaired tongue and mouth behavior. The saliva collected in the mouth can cause salivation of the lips or in the posterior pharynx. During the day it may happen that saliva gets into the trachea which may result in breathing difficulties caused by heavy coughing.
While sleeping, I′m not able to swallow the saliva that gathers in the throat which leads to serious insomnia, even though I′m lying with my head in a higher position, the accumulating saliva gets slimy and thick which prevents normal breathing that causes poor sleep. Also malfunction of the tongue as it drops into the pharynx leads to a feeling as if something is in the throat and sleep disturbance is the result.
By neurological disorders, such as PLS, where the swallowing mechanisms are disturbed and the lips and mouth are impaired, there are often problems with swallowing.