Kidney Stones in Dogs: Symptoms and When to Call Your Veterinarian

Kidney stones are hard mineral deposits that form within a dog’s kidneys.

They vary in size and shape but they can cause worrisome symptoms, such as decreased appetite, abdominal pain, and increased thirst in affected dogs. 

What Are Kidney Stones in Dogs?

Kidney stones are made up of different types of minerals like calcium, magnesium, and phosphorus. They can develop for a variety of reasons, including genetics, diet, and infections. 

Sometimes kidney stones pass through the urine on their own, while other times they get stuck in the ureters, tubes that carry urine from the kidneys to the urinary bladder.  

When this occurs, they can become life-threatening and require emergency veterinary attention.  

Symptoms of Kidney Stones in Dogs

Symptoms of kidney stones in dogs can include:  

• Abdominal pain 

• Decreased appetite 

• Increased thirst 

• Blood-tinged urine 

• Straining to urinate 

• Urinating small amounts frequently 

• Vomiting 

• Lethargy 

• Weight loss 

Causes of Kidney Stones in Dogs

Kidney stones in dogs can be caused by various underlying issues, which include: 

• High mineral diet: Dogs eating diets high in magnesium, phosphorus, and calcium are more likely to develop kidney stones. 

• Dehydration: Dogs who do not drink enough water can have highly concentrated urine, which can lead to stone formation. 

• Kidney infection: A urinary tract infection can become severe and travel to the kidneys if left untreated. This can increase the risk for kidney stones.  

• Abnormal urine pH: If the urine pH is abnormally high or low, crystals can begin to form and solidify into stones.  

• Medications: Some medications, such as furosemide, change the urine composition to be more likely to form stones.  

• Underlying health conditions: Chronic diseases can increase the risk of kidney stones. Diabetes mellitus and inflammatory bowel disease (IBD) are examples.  

Female dogs are more likely to develop kidney stones, likely due to genetics.

Small and toy breed dogs, such as Yorkshire Terriers or Pomeranians, are also at increased risk.  

How Veterinarians Diagnose Kidney Stones in Dogs

A veterinarian first starts with a complete physical exam to identify obvious abnormalities, such as abdominal pain or weight loss.

Pet parents will be asked to describe the concerning symptoms, when they started, and their dog’s daily diet.  

If your veterinarian suspects kidney stones, they may perform the following diagnostic tests:  

• Blood work: A small sample of blood is collected to check kidney function and identify signs of infection or inflammation. 

• Urinalysis: A sample of urine is collected to check for abnormalities, such as bacteria, crystals, or unusual pH levels.  

• X-rays: Images of the dog’s abdomen can be taken to look for bright white areas near the kidneys and bladder, which could indicate stones.  

• Ultrasound: A small probe can be placed onto your dog’s belly to look for kidney stones using sound waves.  

Treatment of Kidney Stones in Dogs

Sometimes, small kidney stones in dogs can pass through into the urine and don’t require any treatment.

Your dog may experience mild discomfort displayed by restlessness, frequently trying to urinate, or they may not show any signs that a stone is passing.  

In other cases, surgery is needed to remove the kidney stones. This is especially true for dogs with multiple or larger stones.  

Additional treatments may be prescribed to treat the underlying cause for the kidney stones, if necessary, which may include:  

• Antibiotics, such as cephalexin, for infections 

• Cranberry supplements, such as VetClassics Cranberry Comfort, to normalize urine pH  

• Anti-inflammatories, such as meloxicam, to reduce inflammation 

• Pain medications, such as gabapentin, to relieve discomfort 

Dogs may need to be switched to a prescription urinary diet, such as Hill’s c/d Multicare Urinary Care, to reduce the risk of recurrence of kidney stones.

This is helpful for stones made of struvite, but may not work well against all types of kidney stones.  

Recovery and Management of Kidney Stones in Dogs

The timing for recovery for dogs with kidney stones varies, depending on the treatment chosen. If a dog undergoes surgery, kidney stones are removed, and the dog is expected to recover within seven to 10 days.  

Pain medication such as meloxicam and antibiotics like amoxicillin may be prescribed. Dogs recovering from surgery may need to wear a recovery cone to prevent them from disrupting their incisions.   

If dissolving the stones using diet or supplements is recommended, it can take several weeks to months for a dog to recover.  

Even after they recover, some dogs may need to be on a prescription urinary diet for the rest of their lives to prevent recurrence of kidney stones. 

Prevention of Kidney Stones in Dogs

To prevent kidney stones in dogs, ensure your dog receives regular wellness care from a veterinarian so they can identify potential health concerns early and begin treatment. 

Feeding your dog a well-balanced diet is important for their overall health and well-being. Likewise, making sure they always have enough fresh, clean water to stay hydrated reduces the risk of stone formation.  

Dogs with a genetic predisposition to stones may benefit from a daily supplement, such as Vetoquinol Methigel Gel Urinary Supplement, that helps keep urine pH levels normal and reduces the risk of stones.