When to euthanize a dog with kidney failure is decided the way it is for any slow illness: by the weeks, scored and compared, and by a vet who knows the disease. Kidney failure tends to show up first in appetite and drinking, which is why those two lines on the quality of life scale do most of the talking.
What kidney failure does to a week
This page won't explain the disease. Your vet has her blood work and will tell you what stage she is at and what that means. What this page can tell you is what families describe, because it is the same few things most of the time.
The water bowl is the first thing. She drinks and drinks and it doesn't seem to help, and then she is up in the night to go out, and then there are accidents from a dog who never had them. Then the food. The kidneys make her feel sick, and a dog who feels sick stops eating, and you start the long work of finding anything she will take: the chicken, the baby food, the thing off your plate. Weight goes. Then the tiredness, the lying in one place, the slow getting up.
On the seven-question scale this site uses, that shows up as hunger and hydration falling first, then hygiene and mobility, with happiness somewhere in the middle. If you are scoring weekly you will see the order. If you are not, start now, because kidney disease in dogs can run for months or turn in a fortnight, and the sheets are how you tell which one you are in.
Fluids, diet, and the question underneath them
Many families end up giving fluids under the skin at home, and changing the diet, and adding whatever the vet prescribes for the nausea. These things work, often for a long time. A dog on fluids can have a good year. That is not what this page is about, and your vet is the one to talk to about any of it.
The question underneath the treatment is the one families don't ask until late, and it's worth asking early. Are the fluids still giving her good days, or only more days? There is a point in kidney failure where the answer changes, and a vet who has seen it many times can usually tell you where you are. Scored weeks help them tell you. A dog whose hunger line has been at two for three weeks despite the fluids is answering the question herself.
Scoring a kidney dog honestly
Two of the seven lines need special care with kidney failure. Hydration is not whether she is drinking. A kidney dog drinks constantly and is still dehydrated, which is why the vet may have you giving fluids under the skin. Score hydration on what the vet tells you about her, and on whether the fluids are keeping her comfortable, not on how often the bowl is empty.
Hunger is the other. Nausea is the thing that takes the appetite, and nausea has its own look: lip-licking, turning the head from food she used to want, drooling, standing over the bowl and walking away. Score the week on whether she ate from the bowl on her own, and tell the vet about the nausea separately, because there are things they can do for it that change the week.
What a crisis looks like
Some dogs with kidney failure decline gently. Some reach a point, often over a day or two, where they stop eating and drinking entirely, vomit what they take, and go very quiet. Ask your vet now, while it is calm, what that would look like for your dog and what you should do if it happens at night. Knowing the emergency number and the plan is a kindness to the version of you who will need it at two in the morning.
If the crisis comes, you are not choosing badly by not having chosen earlier. Many families with a kidney dog hoped for the gentle version and got the other. The scale will have shown you the direction, and the vet will have told you it could turn. That is as prepared as it is possible to be.
Choosing a day
With a slow kidney decline, there is usually time to choose. Families who choose a day while she can still enjoy the chicken get a last day with chicken in it. Families who wait for the nausea to take the last of her appetite get a last day that is mostly relief. Both are allowed. The first is often kinder, and the vets who do this work will say so if you ask.
The page on cancer goes through choosing a day in more detail, and most of it holds here, because the shape of a slow illness is the shape of a slow illness whatever the organ.
Afterwards
A kidney dog leaves a lot behind: the fluid bags, the special food, the syringes in the drawer. You will find them for weeks. Leave them until you are ready, and then ask the vet whether they can pass on what's unopened to someone who needs it.
There are poems written for the day a dog passes, including one for the people who had to decide. And if you want a place for her name and her photo that isn't a phone or a drawer, you can make a page for her when you're ready. Not before.
Questions people sometimes ask
How long can a dog live with kidney failure?
That depends on the stage, the cause, and how the dog responds to fluids and diet, and it is a question for your vet, who has the blood values. Some dogs live comfortably for a long time with managed chronic kidney disease. Some decline over weeks. The scale is for seeing which is happening.
Which signs matter most with kidney failure?
Families most often name appetite and drinking, because the kidneys affect both directly. Nausea that stops a dog eating, and thirst that no amount of water seems to satisfy, are the two that change the week. Mobility and hygiene often follow as the dog weakens.
Should I keep giving fluids at home?
Ask your vet. Fluids under the skin help many dogs feel better for a long time. The question to ask is whether the fluids are still giving her good days or only more days, and your vet can usually tell you honestly.
Does this apply to cats with kidney disease?
The seven areas apply to cats too, and kidney disease is common in older cats. This page is written for dogs, so ask your vet what to watch for in a cat.