Cat has smelly drool in sleep

Question
Sometimes when my cat sleeps, she drools, and I find it adorable. But today, I noticed she was leaving massive puddles of drool that just smelled absolutely awful, almost body odor-like, which the smell would fill the room. And this was only after about 15 minutes of sleeping. She seems to be acting a bit off today, very lethargic and out of it. My friend says it might be just a bad hairball, which is what I'm hoping for, because she is a very old cat, and up until today, seemed to be in the best health I've ever seen in a cat this old.

Answer
Nate,

There are a number of things that can cause foul smelling drool including dental disease, kidney/liver issues... I would suggest having your kitty checked out by a veterinarian just to rule out anything more serious. Typically hairballs result in vomiting, not foul breath/stinky drool. If you have any further questions or concerns, please don't hesitate to contact me again at any time - I'm more than happy to help in any way that I can.

Kind regards,

Ali