Dog Peeing Blood: Causes, Emergency Signs & What To Do

Seeing blood in your dog's urine — medically called hematuria — is unsettling, and for good reason: it's always a sign that something needs veterinary attention. The reassuring part is that it's not always an emergency. Many cases turn out to be a treatable urinary tract infection or early-stage bladder stones. But because the same symptom can also point to something more serious, prompt evaluation matters every time.

This article is for general information only and isn't a substitute for veterinary care. If your dog is straining to urinate and nothing is coming out, that's a medical emergency — don't wait.

What Hematuria Can Look Like

Blood in urine can appear pink, red, rust-colored, or brown, and isn't always obvious to the naked eye — sometimes it's only detected through a urinalysis at the vet's office. A few patterns can offer clues, though they're not a substitute for actual diagnostic testing:

Bright red blood at the very start of urination — often points toward the lower urinary tract, urethra, or prostate
Blood present throughout the entire stream — typically originates from the bladder or higher
Dark brown or tea-colored urine — may indicate bleeding from the kidneys or a condition affecting red blood cells

Common Causes

Urinary tract infections (UTIs) — By far the most common cause of blood in dog urine, especially in female dogs. Bacteria irritate the lining of the bladder and urethra, causing inflammation and bleeding. Dogs with a UTI often strain to urinate, ask to go out more frequently, or have accidents indoors.

Bladder stones — Minerals in the urine crystallize and clump together, ranging from tiny grains to larger stones. As they move through the urinary tract, they can irritate the bladder wall and cause bleeding, straining, or discomfort. In severe cases, stones can fully block urine flow — a life-threatening emergency.

Trauma — A car accident, fall, or other injury can cause internal bleeding that shows up as blood in the urine.

Prostate issues (in male dogs) — Particularly in unneutered males, an enlarged prostate, prostate infection, or prostate tumor can cause hematuria, often alongside straining or changes in gait. Neutering significantly reduces the risk of prostate-related causes.

Bladder or urinary tract cancer — More common in older dogs, and can produce symptoms very similar to a UTI, which is part of why persistent or recurring hematuria always deserves proper diagnostic testing rather than assuming "it's probably just an infection."

Clotting disorders — Some dogs have conditions affecting their blood's ability to clot properly, which can lead to bleeding, including in the urine, even without an obvious injury.

Hereditary (familial) hematuria — More often seen in younger dogs, this is a hereditary condition rather than an acquired one.

Toxin ingestion — Certain toxins (including some rodenticides) can affect clotting and lead to blood appearing in the urine.

A dog in heat — If you have an unspayed female dog, blood-tinged discharge during a heat cycle (which typically lasts 2-3 weeks) can come from the reproductive tract rather than the urinary system, and isn't the same as true hematuria — though if you're not sure which it is, it's still worth a vet check to confirm.

Some conditions can also cause blood in stool at the same time, so it's worth mentioning both symptoms together to your vet.

Age and Sex Can Offer Clues

Younger dogs: hereditary hematuria is a more likely consideration
Older dogs: cancer becomes a more significant possibility, which is part of why persistent hematuria in a senior dog warrants thorough diagnostic workup
Female dogs: more prone to UTIs
Intact male dogs: more prone to prostate-related causes

Is It an Emergency?

Seek emergency care immediately if:

Your dog is straining to urinate but nothing (or very little) is coming out — this suggests a possible blockage and is a true emergency
Bloody urine is accompanied by lethargy, vomiting, depression, or decreased appetite
There's known trauma or possible toxin exposure
You see blood clots or dark red urine

See your vet within 24 hours if:

Your dog is otherwise acting normal but you've noticed blood in the urine, even without other symptoms
Also check for pale gums, which can be another sign your dog needs urgent veterinary attention.

A dog peeing blood while otherwise behaving normally may just have a UTI or early bladder stones — treatable, but still something that needs a vet visit rather than a wait-and-see approach, since it generally won't resolve on its own.

How It's Diagnosed

A urinalysis is the standard first step — your vet examines the urine under a microscope to confirm red blood cells and look for signs of infection, crystals, or other abnormalities. Depending on what's suspected, further testing might include bloodwork, imaging (X-rays or ultrasound) to check for stones or masses, or a urine culture to identify a specific infection.

Treatment Depends on the Cause

UTI — typically antibiotics
Bladder stones — may range from a diet change (to help dissolve certain stone types) to surgical removal, depending on size and type
Prostate issues — may include neutering, along with treatment for any underlying infection
Trauma or toxin exposure — emergency stabilization and targeted treatment
Cancer — further workup to determine staging and appropriate treatment options

Prevention Tips

Feed a high-quality diet appropriate for your dog, since diet plays a role in urine pH and crystal/stone formation
Ensure fresh water is always available
Neuter male dogs (talk to your vet about appropriate timing) to reduce prostate-related risk
Pet-proof your home and yard — secure rodenticides, antifreeze, medications, and toxic plants
If your dog has had recurring UTIs or crystals, ask your vet about a urinary-support diet or supplement suited to your dog's specific needs

Frequently Asked Questions

Can a UTI go away on its own without treatment? It's not something to count on — hematuria generally needs veterinary treatment to resolve, and an untreated UTI can worsen or spread to the kidneys over time.

My dog's urine looks slightly pink but they're acting completely normal — do I still need to go in? Yes, still see your vet within 24 hours. Even without other symptoms, hematuria signals something happening in the urinary system that won't necessarily resolve on its own.

Is blood in urine more common in male or female dogs? Female dogs are more prone to UTIs, one of the most common causes of hematuria. Intact male dogs are more prone to prostate-related causes. Either way, the underlying cause needs to be identified by a vet rather than assumed based on sex alone.