Hi. How high a dosage of glucosamine chondroitin was she on? For my 70 lb. greyhound, the vet said he needs 1500 mg daily, in addition to the 400 mg of devils claw. And the devils' claw made a huge difference in my female, who's now totally pain free. For the cognitive dysfunction problem, and although I'm of course not a vet, all of her symptoms point to that, there's a drug called Anipryl which is used to treat people with Parkinson's that has been used to dramatically improve the quality of life for older dogs.
As far as incontinence - is she spayed? Because there's a hormane-related incontinence which occurs in older, spayed females and there's treatment for that, too. There's a drug which increases the tone of a dog's urethral sphincter.
I can't comment on the drugs she's currently on because I've never had a dog on them and am not quite sure what they're for.
Since I've started taking my aging greyhounds with their myriad skeletal problems to a vet who does chiropractic and acupuncture treatments on dogs, I swear by them. The difference to my guys is dramatic. Is your sister maybe amenable to finding a vet who's more proactive in helping this dog, and if so, perhaps she could benefit from some of these treatments as well.
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