What Are Kidney Stones in Dogs, and What Can I Do About It?

If your dog has been straining to urinate, crying out in pain, or passing blood in their urine, kidney stones might be on your mind. It’s a scary thing to Google at midnight, and you deserve a straight answer: kidney stones in dogs are real, they range from a minor finding to a life-threatening emergency, and knowing the difference matters a lot.

What are kidney stones in dogs?

Kidney stones (medically called nephroliths) are hard mineral deposits that form inside the kidneys when certain minerals in the urine become so concentrated that they start to crystallize and clump together. Think of it like hard water leaving mineral deposits in a pipe, except it’s happening inside your dog’s kidneys.

The kidneys’ job is to filter waste from the blood and produce urine. When the mineral balance in that urine gets disrupted, whether from dehydration, infection, diet, or genetics, crystals can start to form and gradually harden into stones. Some stay small and cause no problems. Others grow large enough to block urine flow, which is where things can get serious fast.

Kidney stones are different from bladder stones, which form in the bladder rather than the kidneys. Both are mineral deposits in the urinary system, but they form in different places, cause different symptoms, and are treated differently. More on that distinction below.

Symptoms of kidney stones in dogs

The tricky part: kidney stones often don’t announce themselves. A dog can carry a stone in their kidney for months without any sign that anything’s wrong.

• Blood in urine: Urine that looks pink, red, or brownish. On its own this could point to several conditions, but it’s always worth a prompt vet visit.
• Straining or whimpering when trying to urinate: A sign of significant discomfort in the urinary tract. Combined with blood in urine, this is a same-day vet call.
• Urinating more frequently but in smaller amounts: The body trying to move something that won’t move easily.
• Pain or tenderness in the lower back or abdomen: Might look like reluctance to move, hunching, or restlessness. If your dog seems uncomfortable in a way they can’t explain, this is worth investigating.
• Vomiting or lethargy: Especially if a stone is blocking urine flow. If your dog is vomiting alongside urinary symptoms, treat it as urgent.
• Loss of appetite or general dullness: A more gradual sign that something systemic is going on.

What causes kidney stones in dogs

Kidney stones (also called nephroliths) form when certain minerals in the urine become so concentrated that they start to crystallize and clump together. A few things make this more likely:

• Dehydration: when a dog doesn’t drink enough water, urine becomes more concentrated, giving minerals a better chance to form crystals
• Urinary tract infections: which can change the chemistry of the urine
• Diet high in certain minerals (calcium, oxalate, purines) depending on the stone type
• Genetics: some breeds are more prone to certain types of stones
• Metabolic conditions like liver disease: closely tied to urate stone formation
• Urine pH: urine that’s consistently too acidic or too alkaline creates the right conditions for specific stone types to grow

Types of kidney stones in dogs

Not all stones are the same, and the type matters because it changes how your vet will approach treatment. Here are the three most common.

Calcium oxalate stones

The most common kidney stones in dogs. They’re hard, dense, and can’t be dissolved with medication, which means they usually require surgical removal if they’re causing problems. Breeds like Miniature Schnauzers, Lhasa Apsos, and Yorkshire Terriers are especially prone. A low-oxalate prescription urinary diet and increased water intake are the main ways to slow new stone formation.

Struvite stones

Almost always tied to a bacterial urinary tract infection. The bacteria change the urine’s pH, making it more alkaline, which allows struvite crystals (made of magnesium, ammonium, and phosphate) to form. The good news: struvite stones can often be dissolved with a prescription urinary diet and antibiotics, without surgery. Once the infection is cleared and the diet is adjusted, the stones typically dissolve over weeks to months.

Urate stones

Less common but worth knowing about, especially if you have a Dalmatian or English Bulldog. They’re linked to how the body processes purines (a naturally occurring compound found in many proteins), and in some breeds, a genetic quirk causes purines to turn into uric acid, which then crystallizes. Liver disease can also drive urate stone formation in any breed. Treatment usually involves a low-purine diet and sometimes medication to reduce uric acid levels.

Kidney stones vs. bladder stones in dogs: what’s the difference?

Both are mineral deposits that form in the urinary system, but where they form, what symptoms they cause, and how urgent they are can be very different.

	Kidney Stones	Bladder Stones
Where they form	Inside the kidneys	Inside the bladder
When they become dangerous	When they move into the ureter (the tube connecting kidney to bladder) and block urine flow	When they move into the urethra (the tube from bladder to outside the body) and cause a blockage
Symptoms	Often none until they move; pain and blood in urine when they do	More likely to cause ongoing symptoms: frequent urination, straining, blood in urine
How commonly diagnosed	Less often, partly because they’re less likely to cause obvious symptoms early	More often, because symptoms tend to show up sooner
Emergency risk	A blocked ureter (ureteral obstruction) can cut off kidney function rapidly	A blocked urethra is also an emergency, and more common in male dogs due to narrower anatomy
Treatment approach	Often requires advanced intervention: stenting, SUB procedure, or surgery	May include non-surgical options like flushing stones back into the bladder, alongside surgery

How vets diagnose kidney stones in dogs

Your vet will typically start with a physical exam and then move to diagnostics.

• Urinalysis: a urine test that checks pH, looks for crystals or blood, and screens for infection. Urine pH is a key clue: certain stones form in acidic urine, others in alkaline urine. A dog fecal test may also be run to rule out other conditions.
• Ultrasound: the most useful imaging tool for seeing kidney stones. It can show the size and location of stones and whether a ureter is blocked.
• X-rays: calcium oxalate and struvite stones are usually visible on X-ray. Urate stones are often not, which is why ultrasound matters. For context on average dog X-ray costs, that’s worth knowing before your appointment.
• Blood work: to check kidney function and look for signs of infection or metabolic disease.
• Stone analysis: if a stone is retrieved, it’s sent to a lab to identify its exact mineral composition, which guides prevention going forward.

Treatment options

Treatment depends on the stone type, its size, its location, and whether it’s causing a blockage.

• Monitoring: Small kidney stones that aren’t blocking anything and aren’t causing symptoms are sometimes watched closely rather than treated immediately. Regular ultrasounds track whether they’re growing or moving.
• Prescription urinary diet: Struvite stones can often be dissolved over weeks to months with the right prescription food that adjusts urine pH and reduces the minerals feeding the stones. Calcium oxalate stones can’t be dissolved this way, but diet still helps prevent new ones from forming.
• Surgery: For large stones or those causing pain and infection, surgical removal (called a nephrolithotomy or ureterotomy, depending on location) may be needed.
• Ureteral stenting: When a stone blocks a ureter, placing a thin tube (a stent) inside the ureter to hold it open is typically the preferred first-line minimally invasive option. This allows urine to flow past the obstruction while the stone is managed.
• Subcutaneous ureteral bypass (SUB): When stenting isn’t feasible or has not resolved the obstruction, vets may place a small implanted bypass device that reroutes urine from the kidney directly to the bladder, bypassing the blocked ureter entirely. It’s a specialized procedure done at veterinary referral centers, but it can be life-saving.
• Antibiotics Prescribed alongside diet changes for struvite stones to clear the underlying infection driving stone formation.

One thing to know: there are no proven home remedies for kidney stones in dogs. While keeping your dog well-hydrated and on a vet-recommended diet is genuinely helpful for prevention and slowing growth, stones that are already causing symptoms need veterinary care, not a wait-and-see approach at home.

How to prevent kidney stones in dogs

Your vet will typically start with a physical exam and then move to diagnostics.

• Urinalysis: a urine test that checks pH, looks for crystals or blood, and screens for infection. Urine pH is a key clue: certain stones form in acidic urine, others in alkaline urine. A dog fecal test may also be run to rule out other conditions.
• Ultrasound: the most useful imaging tool for seeing kidney stones. It can show the size and location of stones and whether a ureter is blocked.
• X-rays: calcium oxalate and struvite stones are usually visible on X-ray. Urate stones are often not, which is why ultrasound matters.
• Blood work: to check kidney function and look for signs of infection or metabolic disease.
• Stone analysis: if a stone is retrieved, it’s sent to a lab to identify its exact mineral composition, which guides prevention going forward.

Does pet insurance cover kidney stones in dogs?

Diagnosing and treating kidney stones can get expensive fast, especially if your dog needs an ultrasound, surgery, or a specialized procedure like a subcutaneous ureteral bypass. The cost of treating a ureteral obstruction at a referral center can run into the thousands.

Kidney stones in dogs are eligible for coverage under a Lemonade accident and illness policy, including diagnostics like urinalysis and imaging, surgery, hospitalization, and specialized procedures like the subcutaneous ureteral bypass, as long as the condition isn’t pre-existing and develops after the 14-day illness waiting period has passed.

If your dog is already showing signs of kidney problems before you enroll, those signs could be considered a pre-existing condition and excluded from coverage. Getting a policy in place while your dog is still healthy is what keeps your options open when it matters most.

Before we go

Kidney stones in dogs run the full spectrum, from a quiet, incidental finding to a genuine emergency. Knowing the signs, understanding the stone types, and keeping up with routine vet visits puts you in the best possible position. If your dog is straining to urinate, passing blood in their urine, or seems to be in pain, don’t wait. Call your vet. And if you don’t already have a pet health insurance policy in place, now is a good time to think about it, before a diagnosis changes what’s coverable.

Frequently Asked Questions

A few quick words, because we <3 our lawyers: This post is general in nature, and any statement in it doesn’t alter the terms, conditions, exclusions, or limitations of the policies issued, which differ according to your state of residence. You’re encouraged to discuss your specific circumstances with your own professional advisors. The purpose of this post is merely to provide you with info and insights you can use to make such discussions more productive! Naturally, all comments by, or references to, third parties represent their own views, and Lemonade assumes no responsibility for them. Coverage may not be available in all states. Please note that statements about coverages, policy management, claims processes, Giveback, and customer support apply to policies underwritten by Lemonade Insurance Company or Metromile Insurance Company, a Lemonade company, sold by Lemonade Insurance Agency, LLC.  The statements do not apply to policies underwritten by other carriers.