Have you checked her gums & teeth?
My Matthew has SM. He has been on frusemide for years & has never had a drooling problem until recently.
He now has a tooth that is very loose, my vet believes it will drop out soon and would prefer not to operate on an eleven year old with a very dodgy heart.
I hope the tooth soon drops out. He is a very damp smelly old boy at the moment.
Cavaliers......Tommy Tuppence 2000-2012 and a half share of Faith.
Japanese Chins.... Dandy, Benny, Bridgette and Hana.