What to do after a CKD diagnosis: your first-week checklist

If you are reading this, someone you love just got a hard diagnosis. Maybe the vet said "kidney disease" and the rest of the appointment went blurry. That is completely normal. Take a breath. You do not have to become an expert tonight.

Chronic kidney disease (CKD) is one of the most common conditions in older cats. It is a long-term condition, not an emergency in most cases, and many cats live good months and often years after diagnosis with thoughtful care at home. The first week is mostly about steadying yourself, understanding the basics, and setting up a few simple routines.

This guide walks you through that week, one small step at a time.

First, what CKD actually means

Your cat's kidneys filter waste out of the blood, balance minerals like phosphorus and potassium, help control blood pressure, and conserve water. In CKD, the kidneys slowly lose some of that ability. The damage that has already happened usually cannot be reversed, but the pace of change can often be slowed, and many of the symptoms can be eased.

Most cats are diagnosed through blood and urine tests. The values you will hear about most are creatinine, SDMA, BUN, phosphorus and urine specific gravity (USG). You can read plain-English explainers for each in our lab value guides, starting with creatinine and SDMA.

Vets often use the IRIS system (from the International Renal Interest Society) to describe where kidney values sit, from Stage 1 to Stage 4. Staging is done by your vet, using more than one test, once your cat is stable and well hydrated. If your vet has mentioned a stage, our IRIS stages overview explains what each one generally means.

Day 1–2: steady yourself and gather information

The single most useful thing you can do in the first two days is collect information, not act on everything at once.

• Ask for a copy of the lab report. Most clinics will email it. Keep every report — trends over time matter more than any single number.
• Write down what your vet said while it is fresh. Medications, food suggestions, the next recheck date.
• Note your cat's weight from the visit. Weight is one of the most useful things to track at home.
• Notice how your cat is today. Appetite, drinking, litter box, energy. You are building a baseline.

If the report feels like alphabet soup, our free Lab Decoder lets you type in the values and see what each one means, alongside the IRIS reference ranges. It does not diagnose or stage your cat — it simply helps you understand the conversation with your vet.

Day 3: understand why food and phosphorus matter

You will hear a lot about diet. Here is the short version.

When kidneys filter less, phosphorus from food can build up in the blood. Keeping phosphorus in a healthy range is one of the best-studied ways to support a CKD cat, and IRIS publishes target ranges for phosphorus at each stage. Your vet will tell you what range they are aiming for. Our phosphorus explainer goes deeper.

Prescription kidney (renal) diets are lower in phosphorus and adjusted in protein and sodium. Studies have linked them to longer survival and fewer kidney crises in cats with CKD, which is why many vets recommend them.

But there is an equally important rule: a cat that eats is the first priority. A cat that refuses food entirely can become seriously ill. So if your cat turns away from a new food, do not try to force it. Talk to your vet, and read what to do when your CKD cat won't eat.

If your vet suggests a renal diet, change slowly — usually over a couple of weeks or more — by mixing a little of the new food into the old. If you want to understand how foods compare, our guide to low-phosphorus diets and reading cat food labels explains it step by step.

Day 4: set up medications calmly

Not every cat needs medication right away. Some cats go home with nothing new. Others may be prescribed things like a phosphate binder, an anti-nausea medicine, a potassium supplement or a blood pressure medicine.

Whatever your vet prescribes, the goal this week is simply to make it routine:

• Write down each medicine exactly as your vet prescribed — name, amount, how often, with or without food.
• Pick fixed times that fit your day.
• If more than one person helps, agree on one place to record each dose so nobody doubles up or skips.
• Ask your vet or vet tech to show you how to give a pill or liquid if you are unsure. Pill pockets, compounded flavours or a pill popper can help.

Never change a dose, stop a medicine or add a supplement without checking with your vet first. Some over-the-counter products — including some human pain medicines — can be harmful to cats, especially cats with kidney disease.

Day 5: water and weight

CKD cats lose more water in their urine than healthy cats. Helping them stay hydrated is one of the kindest everyday things you can do.

• Offer wet food if your cat will eat it. It carries a lot of water.
• Put extra water bowls around the house, away from food and litter.
• Try a water fountain — some cats drink more from moving water.
• Wide, shallow bowls suit cats who dislike their whiskers touching the sides.

Some cats will eventually need extra fluids given under the skin at home. If your vet mentions this, our subcutaneous fluids guide explains what it involves. It sounds daunting, but most owners become comfortable with it.

Then, weigh your cat. Weigh yourself holding your cat, then without; the difference is your cat's weight. A digital baby scale is even more accurate. Write it down with the date. A slow, steady weight loss is easy to miss by eye and very useful for your vet to know about.

Day 6: prepare for the unexpected

While things are calm, take ten minutes to prepare for a bad night. You will be glad you did.

• Save your vet's number and the nearest 24-hour emergency clinic in your phone.
• Write down your cat's medicines and the date of the last blood test.
• Know the signs that mean "call now": not eating for a day or more, repeated vomiting, collapse, seizures, straining with no urine, sudden blindness, or breathing trouble.

Our free Is my cat okay? guide walks you through common worries and helps you decide whether to call your vet now, today, or keep watching. It always errs on the side of caution.

Day 7: look back, and plan the long game

One week in, you know your cat's patterns better than you did seven days ago. That knowledge is genuinely valuable.

Spend a few minutes looking back at what you have noticed: appetite, weight, drinking, energy, litter box. Write down anything that changed. Bring it to your next visit along with your questions.

Then think about the next few months. CKD care is a long game, and the most helpful habits are small and repeatable: logging appetite and weight, rechecking labs on the schedule your vet sets, asking about blood pressure, and keeping food and medicines steady. Our printable fluid and medication log is a simple way to start.

Your first-week checklist

Print this, tick it off, and remember: none of it has to be perfect.

• Get a copy of every lab report and keep them together
• Write down what your vet said, and the date of the next recheck
• Look up each lab value in plain English (try the Lab Decoder)
• Ask whether blood pressure and a urine protein (UPC) test have been checked
• Ask your vet whether a diet change is right now, and how to transition slowly
• Write down each medicine exactly as prescribed, with set times
• Put out extra water bowls or a fountain
• Weigh your cat and record the date
• Save your vet and 24-hour emergency clinic numbers
• Note appetite, drinking, litter box and energy each day
• Write a list of questions for your next visit
• Do something kind for yourself, too

You are not alone in this

A CKD diagnosis can bring a wave of guilt — "should I have noticed sooner?" Please be gentle with yourself. Cats are experts at hiding illness, and early kidney changes are often invisible without bloodwork. The fact that you are reading this means your cat has someone paying attention.

Build a small team: your vet, a vet tech who can help with practical skills, and perhaps a feline-focused practice or an internal medicine specialist if questions get complex. Ask questions as often as you need to. Good vets expect it.

This information is general and is not a substitute for your veterinarian's advice. Your vet knows your cat and will guide decisions about tests, food and treatment.

Sources & further reading

• International Renal Interest Society (IRIS) — CKD staging and treatment recommendations
• Cornell Feline Health Center — Owner information on feline chronic kidney disease
• International Society of Feline Medicine (ISFM) / International Cat Care — ISFM consensus guidelines on feline CKD
• VCA Animal Hospitals — Client education on kidney disease in cats