I have a 14 years old Bearded Collie. Only 2 weeks ago she was full of spunk but a few days ago stopped eating and lay down very luthargic. Every few hours she strains to stand up, her hind legs are obviously wobbly, and, she will take a few steps and than lay down again. She is fairly alert to sights and sounds but seem to be shutting down. What puzzles me the most is that she will readily drink water in large quantities when offered but absolutley refuses any food, not even steak!
Is she shutting down or does anyone think that her refusal to eat may be caused by some other unrelated medical problem?
Thanks for any thought or help in this matter. I am very concerned and upset right now.

Please take your dog to the vet asap!

Excessive drinking can be the symptom of many conditions.
Unfortunately your dog is towards the end of her life and diseases are a lot more common...

Get her to the vet to see if there is any medication that can hopefully fix her illness or at least make her more comfortable :)

This happened to my moms staffy. Unfortunately all it was was old age and it was time to let her go. Your dog is old so prepare yourself cause this may be the case. Sorry if it is!

I hope that by now you have called your vet, she is 14, it sounds like she is shutting down, and kidneys are failing, the first thing they do before they go, is stop eating, usually its due to their kidneys shutting down, it is painful for them, you need to make sure your consulting with your vet, back and hips could be a huge part of this too, but either way, it sounds like there is un-necessary suffering, 14 years old is a good long life, lethargic behavior can be to kidney failure , it usually does that.