Trends

Vet Column

2026-07-23

What Is Chronic Kidney Disease (CKD) in Dogs and Cats? How Can You Detect It Before Symptoms Appear?

fish-oil digestive problems dog cat kidney disease urinary problems

This article was written by Dr. Shang-Hsiu Chung, a veterinarian at Always Care Veterinary Hospital

"My pet eats normally and seems active. How could a routine health check reveal kidney disease?"
This is one of the most common questions veterinarians hear from pet owners.
The biggest challenge of chronic kidney disease (CKD) in dogs and cats is that it often develops silently.
Because the kidneys have remarkable compensatory capacity, pets can continue living normally even after a significant decline in kidney function.
As a result, many owners do not notice any abnormalities until their dog starts drinking excessive amounts of water, urinating more frequently, losing weight, or showing a reduced appetite. Unfortunately, by this stage, kidney damage has usually been progressing for quite some time.

Chronic Kidney Disease (CKD) is one of the most common chronic illnesses affecting senior dogs and cats. It is estimated to affect approximately 5–10% of older dogs and 30–60% of older cats.
Although CKD cannot be cured, clinical studies have shown that early detection, regular monitoring, appropriate nutrition, and dietary management can significantly slow disease progression and help pets maintain a good quality of life.

In 2023, the International Renal Interest Society (IRIS) updated its guidelines, recommending the combined evaluation of serum creatinine (Creatinine) and Symmetric Dimethylarginine (SDMA) to assess kidney function. Compared with creatinine alone, SDMA can detect reduced kidney function earlier, making it a valuable biomarker for early diagnosis.
What Are the Symptoms of Kidney Disease in Dogs and Cats?

Early-stage CKD often causes few or no obvious symptoms.
The earliest clinical signs commonly include:

Increased water consumption (polydipsia)
Increased urination (polyuria)

As kidney disease progresses, pets may develop:

Reduced appetite
Weight loss
Lethargy
Vomiting
Bad breath (uremic odor)

If your dog or cat is drinking noticeably more water, urinating frequently, losing weight, or experiencing a persistent decrease in appetite, schedule a veterinary examination as soon as possible instead of waiting for symptoms to worsen.
Veterinarians typically diagnose CKD through:

Blood tests (Creatinine and SDMA)
Urinalysis
Diagnostic imaging (such as ultrasound or radiography)

The disease is then staged according to IRIS CKD Guidelines, providing the foundation for long-term treatment and nutritional management.
Since CKD is an irreversible condition, ongoing dietary management and nutritional support play essential roles alongside veterinary treatment.

What Should Dogs and Cats with Kidney Disease Eat?

Nutritional Management Is the Key to Slowing CKD Progression
Research consistently demonstrates that renal therapeutic diets are among the most effective nutritional strategies for slowing CKD progression.
Prescription kidney diets have been shown to:

Extend survival time
Slow the decline in kidney function
Improve overall quality of life

Among all dietary modifications, phosphorus restriction is considered the single most important nutritional intervention.
Therefore, the IRIS Guidelines recommend gradually transitioning Stage 2 CKD patients and beyond to renal therapeutic diets whenever possible.

Restrict Phosphorus Intake
High dietary phosphorus accelerates kidney damage.
Foods naturally high in phosphorus—including organ meats, bones, dried fish, and certain treats—should be limited, while prescription renal diets are specifically formulated to reduce phosphorus intake and lessen the kidneys' workload.

Choose High-Quality Protein Instead of Simply Reducing Protein
Many pet owners worry that protein harms the kidneys.
In reality, protein quality matters more than protein quantity.
Highly digestible, high-biological-value proteins generate fewer uremic toxins while helping maintain muscle mass and preventing malnutrition.

Encourage Adequate Water Intake
Proper hydration is equally important.
Veterinarians often recommend:

Feeding more wet food
Using pet water fountains
Placing multiple water bowls around the home
Softening dry kibble with water

Adequate hydration supports metabolism and reduces the risk of dehydration.
In recent years, nutritional supplements have also become increasingly recognized as valuable adjuncts to kidney health management.

Which Supplements Support Kidney Health in Dogs and Cats?

Although supplements cannot replace veterinary treatment or prescription diets, they may provide valuable nutritional support when used appropriately.
The most extensively studied ingredients include:

Omega-3

EPA and DHA possess anti-inflammatory properties, help reduce oxidative stress, and support healthy renal blood flow.
Because of their strong scientific evidence, Omega-3 fatty acids are widely incorporated into prescription kidney diets and renal support supplements.

Probiotics

CKD can alter the intestinal microbiome.
Some studies suggest that probiotics such as Lactobacillus acidophilus and Enterococcus faecium may help maintain gut health and reduce the production of certain uremic toxin precursors.

However, probiotics should be considered supportive nutrition rather than a replacement for medical treatment.

Vitamin B Complex

Because pets with CKD often lose water-soluble B vitamins through increased urination, supplementation may help support:

Energy metabolism
Appetite
Nervous system function

Vitamin B complex is therefore commonly included in renal support formulas.

Antioxidants

Oxidative stress contributes to kidney aging and chronic inflammation.
Antioxidants such as Vitamin E may help protect cells from free radical damage and support overall kidney health.
However, if pets develop complications such as hyperphosphatemia, hypokalemia, or metabolic acidosis, supplementation should always be adjusted under veterinary supervision.

Can Chronic Kidney Disease Be Prevented?

Although CKD cannot always be prevented, several lifestyle measures may reduce the risk:

Provide unlimited access to clean drinking water.
Maintain an ideal body weight.
Feed a balanced diet.
Avoid prolonged use of medications that may impair kidney function unless prescribed.
Schedule routine wellness examinations for pets over seven years of age.

For pets already diagnosed with CKD, owners should:

Follow veterinary treatment recommendations.
Feed prescription renal diets.
Encourage adequate water intake.
Monitor daily water consumption, urination, appetite, and body weight.
Attend regular follow-up examinations.

Early intervention remains the most effective strategy for slowing disease progression and maintaining quality of life.

Supporting Long-Term Kidney Health

Although chronic kidney disease cannot be reversed, early diagnosis combined with appropriate nutritional management can significantly improve long-term outcomes.
Current evidence supports a comprehensive management approach that includes:

Routine health screenings
Low-phosphorus nutrition
High-quality protein
Omega-3 fatty acids
Regular veterinary monitoring

Because early CKD often develops without noticeable symptoms, proactive screening and timely intervention remain the best ways to protect your pet's kidney health and preserve their quality of life.

Welpet specializes in the research, development, and manufacturing of premium pet nutritional supplements. By continuously monitoring emerging trends in canine and feline kidney health, Welpet provides innovative functional ingredients and customized product development solutions, helping pet brands create scientifically formulated kidney support products that meet evolving market demands.

Q1. Does excessive drinking and urination always mean kidney disease?
Not necessarily. Increased thirst and urination may also be caused by diabetes mellitus, Cushing's disease, pyometra, liver disease, or simply increased water intake. If these symptoms persist for several days, consult your veterinarian for blood and urine testing to determine the underlying cause.

Q2. Can chronic kidney disease in dogs and cats be cured?
No. CKD is an irreversible disease. However, early diagnosis combined with prescription renal diets, appropriate nutritional support, and regular veterinary monitoring can help slow disease progression and maintain a good quality of life.

Q3. Does every pet with CKD need a prescription renal diet?
Most veterinarians recommend transitioning pets diagnosed with IRIS Stage 2 CKD or higher to prescription renal diets whenever possible. These diets typically contain reduced phosphorus, moderate amounts of highly digestible protein, and added Omega-3 fatty acids. Dietary recommendations should always be individualized according to veterinary assessment and the pet's acceptance of the diet.

Q4. Can pets with kidney disease take nutritional supplements?
Yes. While supplements cannot replace veterinary treatment or prescription diets, research suggests that Omega-3 fatty acids, probiotics, Vitamin B complex, and antioxidants may provide valuable nutritional support. Supplement selection should always follow veterinary guidance.

Q5. How can I help prevent chronic kidney disease?
Because early CKD often has no obvious symptoms, annual wellness examinations—including blood and urine testing—are recommended for dogs and cats over seven years of age. Providing adequate hydration, maintaining a healthy weight, feeding a balanced diet, and avoiding unnecessary nephrotoxic medications may also help reduce the risk of kidney disease.

fish-oil digestive problems dog cat kidney disease urinary problems

next>

Dog Hip Dysplasia: Symptoms, Causes, Diagnosis, and Joint Care Tips

BACK

Products

Urinary Care

Uninary hesitance due to inflammation or kidney stones

Urinary Care

Uninary Hesitance due to Inflammation or Kidney Stones

more news

Vet Column

2026-06-23

Dog Hip Dysplasia: Symptoms, Causes, Diagnosis, and Joint Care Tips

When your dog starts becoming less active, walks more slowly, or shows signs of dog back leg weakness and difficulty standing up, many pet owners assume it is simply a natural part of aging. However, these seemingly normal age-related changes may actually be signs of one of the most common orthopedic conditions in dogs—Dog Hip Dysplasia, also known as Canine Hip Dysplasia (CHD). Hip dysplasia is not a condition limited to senior dogs. Many high-risk breeds begin developing joint laxity during puppyhood. Without early detection and proper management, the condition can progress to osteoarthritis, chronic pain, and reduced mobility, significantly affecting a dog's quality of life.

Vet Column

2026-06-01

Is Pet Fish Oil Worth It? Understanding Omega-3 Benefits, Selection Tips, and Safe Supplementation

In recent years, more and more pet owners have started supplementing their dogs’ and cats’ diets with fish oil. Whether it is for skin allergies, excessive shedding, joint degeneration, or cardiovascular support for senior pets, fish oil has become one of the most popular nutritional supplements available today. However, many pet owners do not realize that the true value of fish oil lies not in the oil itself, but in the Omega-3 fatty acids it provides. EPA and DHA are the key nutrients responsible for most of the health benefits associated with fish oil supplementation.