Coughing up huge amounts of saliva

Hi, this in relation to my 86 year old Dad. He has bouts of ‘throwing up’ huge amounts of saliva. We think it’s saliva, it’s clear, odourless, liquid but looks gloopy, quite thick. It goes on for hours and occasionally through the night. GP not interested and he’s never seen a consultant or MS nurse for anything. We have tried hyoscine to dry up the saliva and it worked but had an adverse affect on his limited mobility so it’s a no no.
These episodes are getting more frequent and this last one has been more than 24 hours, he’s not eaten or drank anything since yesterday afternoon. Has anyone had any similar experience?
His throat is always full and he can’t swallow hard or cough up. His nose is also constantly dripping.
Any ideas? Any suggestions?
All advice appreciated. Thanks in advance

Hi don’t know if it’s the same as my problem on occasions I suffer with a horrible cough and cough up large amounts of clear gloopy liquid also suffer with a sore throat and definitely go off my food I’ve been told its most likely gastro oesophageal reflux “GERD” for short It’s stomach acid in my case where you produce a large amount of gastric acid in the stomach this causes reflux and you can develop a cough as I described above It can also be caused by a stomach ulcer so I have been told I need an endoscopy to investigate Your poor Dad sounds awful I hope he gets better soon, Jane

Hi
It’s possible it’s a side effect of some medication. I take sertraline, and have noticed that if I take it later in the day, or if I missed it for a few days, my throat feels a little sore and I generate a load of saliva to spit out for a a couple of hours. So I’d check the side effects of all his meds.

Dan