What Could Cause Sudden Excessive Drooling, Lethargy, Loss Of Appetite, And Persistent Hiccups In A Parkinson’s Patient With A Suprapubic Catheter?

My husband has had Parkinson s Disease for about 13 years, and currently has a suprapubic catheter to manage his urinary retention. He has been hospitalized with UTI s, severe constipation (manual removal needed), stercoral colitis, and sepsis. Sometimes he drools, which we attribute to PD and infrequent swallowing. Yesterday he awoke feeling lethargic and weak. He was drooling excessively (unusual for him). The drool was viscous but clear. He developed hiccups that lasted all day. He didn t want to eat anything at all. His vital signs and temperature were all normal. What could have precipitated this episode? Which medications for excess salivation would be safe for someone with his issues? He also is on daily Sinemet, memantine (Namenda), rivastigmine (Exelon patch), Fosfomycin (to prevent UTI), Florinef (to raise his BP), and is on a bowel regimen of Miralax, Senna and Colace.