You raise several important issues.
First of all, while kidney disease may make animals (and people) feel lousy (weakness, dehydration), in and of it itself it is not a painful disease. Some sequelae (consequences) of it can be painful such as stomach ulcers, oral ulcers, movement of uroliths (stones) or blockage of urinary pathways by such stones. It is not clear from your post why the dog is taking pain relief medication in the first place.
Morphine, hydromorphone, oxymorphone, tramadol, oxycontin and other drugs in this class are not uncommonly used for pain in animals. Dose frequency, available forms and sizes, route of administration, onset and duration of action and other considerations play into the choice of pain reliever.
I would need to know more about why your dog is on pain relief medication to comment, as there must be more going on than kidney disease.
Dr. Arnie Goldman
I completely agree with Dr Goldman and wanted to add that dogs mourn just like people after the loss of a companion. We recommend lots of extra love, attention and TLC while going through the normal phases of the grieving process and have found this to be helpful for both the owners and pets.
Dr carol Osborne, DVM
Greetings - -
I am sorry to learn of your friend's discomfort...
"...My aussie ...is in so much pain that he groans all day,I tried Tramadol last night but had no effect on the pain. Can dogs take morphine when they have kidney failure?..."
The very first and most important step is to have this dog's pain diagnosed... where is it, why is it occurring, etc... Without this critical information no rational decisions can be made.
Once the pain is better understood, then a reasonable and appropriate pain management strategy can be put into place. It is true that narcotic pain relievers can be used, but I rarely reach for them except for the acute pain around surgery... There are other choices that probably make more sense from the perspective of therapy targeting specific areas of the nervous system.
I can certainly assist your primary care veterinarian in making good decisions on behalf of your dog should this discomfort persist.
Celebrating, protecting, and sharing the special love of animals,
Robin Downing, DVM
Certified Veterinary Acupuncturist
Certified Canine Rehabilitation Practitioner
Certified Pain Educator
Diplomate, American Academy of Pain Management
The Downing Center for Animal Pain Management, LLC
Windsor Veterinary Clinic, PC
415 Main Street
I just want to add that you assume your dog is in pain. As Dr. Goldman said, kidney disease does not normally present with pain. With the recent loss, the hiding and groans you see may (I say may) be psychological. The feeling of loss, loneliness, loss of "pack integrity", etc. May also be arthritis or another cause of pain not related to kidney disease.
A good physical exam is in order and a discussion with your vet about they find.
IF this is a psychological issue, then a "jolly" routine might work. This is overtly happy play, distraction, chase ball, walks, dog park visits etc. And them TIME will heal the loss.
So An exam to rule out real medical problems and perhaps Dr. Downing's kind offer of pain management assistance (she is a respected authority). If no doctor can find a reason for physical pain, then let's focus on her mental health!!
Thanks to all doctors who gave great answers here!!!