Blood in Dog Urine: Causes, Symptoms and What to Do

Seeing blood in dog urine (the medical term is haematuria) should ring alarm bells for any UK pet parent. Whether the pee looks pink, red or cola-brown, it means blood cells are leaking somewhere in your dog’s urinary system. The most common culprits are a urinary tract infection, bladder stones or, less often, a tumour. A same-day vet call is always the safest move. In the meantime, collect a fresh urine sample, note other symptoms (straining, frequent urination, weight loss, exposure to rat poison) and keep your dog calm and hydrated. The faster you act, the better your vet can protect the kidneys and rule out life-threatening problems.

What Is Blood in Dog Urine?

Haematuria means red blood cells have escaped into your dog’s urine. Vets divide it into:

• Lower urinary tract sources – bladder, urethra and, in male dogs, the prostate.

• Upper urinary tract sources – kidneys or ureters.

Sometimes you only notice blood at the naked eye level; other times it’s microscopic and picked up on a urine test. UK charity PDSA lists haematuria, frequent urination and smelly urine as classic flags for bladder trouble. If you spot any colour change—pink, rusty or coffee-brown—assume bleeding until proven otherwise.

Is Blood in Dog Urine a Sign of Cancer?

Sometimes, yes. Bladder cancer—usually transitional cell carcinoma (TCC)—and kidney cancer can both cause persistent blood in dog urine. The Royal Veterinary College notes that cancers of the urinary tract are more likely in older dogs and certain terrier breeds, and they often present with haematuria plus straining or weight loss. Visible blood occurs in roughly half of TCC cases reported in clinical papers. Early imaging (ultrasound or contrast X-ray) can spot small masses while surgery or chemotherapy can still help. Because tumours can mimic chronic urinary infection, any “UTI” that keeps coming back after antibiotics deserves a deeper look with cytology or biopsy.

If your vet mentions a possible mass, don’t panic—but do act quickly. Collect past lab results, agree on next diagnostic tests, and discuss referral to an oncology service if imaging confirms cancer. Prompt action improves comfort and can extend good-quality life.

Is Blood in Dog Urine an Emergency?

Yes—treat blood in dog urine as an emergency until a vet rules out life-threatening causes. Even if your dog seems comfortable, unseen problems can worsen fast. A urinary tract infection can climb to the kidneys in hours, while bladder stones may shift and block the urethra, stopping your dog from passing urine at all.

Bleeding caused by rat poison or other clotting disorders is equally urgent because internal haemorrhage doesn’t stop on its own. The RSPCA’s first-aid pages stress staying calm, collecting a urine sample if possible, and contacting a vet immediately whenever you notice sudden bleeding or any sign your dog is peeing blood.

Causes of Blood in Dog Urine

Seeing blood in dog urine—also called haematuria—is often alarming. It means red blood cells are leaking into the urinary tract, but the exact source and cause can vary. The bleeding might come from the lower urinary tract, like the bladder or urethra, or from the upper urinary tract, such as the kidneys or ureters. To find the right treatment plan, your vet needs to identify the underlying cause. Here are the most common ones:

1. Urinary Tract Infections (UTIs)

A urinary tract infection is the most common reason for a dog peeing blood. It usually starts in the bladder and is caused by a bacterial infection. When bacteria enter the lower urinary tract, they cause inflammation that damages the lining, leading to bleeding. You might also notice other symptoms like frequent urination, straining to pee, or a strong-smelling odour in the urine. UTIs are more common in female dogs, but male dogs can get them too. Left untreated, the infection can spread upward, turning into a kidney infection. According to the PDSA, UTIs are among the most frequently diagnosed urinary tract problems in UK dogs.

2. Bladder and Kidney Stones

Bladder stones and kidney stones are another major cause. These stones form when minerals in the urinary system clump together and harden. Over time, they can rub against the bladder wall or block the urethra, causing irritation and bleeding. Dogs may strain to urinate, pass only small amounts, or have accidents indoors. In severe cases, the dog may be unable to pass urine, which is an emergency. Some stones can dissolve with special diets, while others require surgery or laser treatment. The Royal Veterinary College notes that stone formation often recurs if not properly managed.

3. Bladder or Kidney Cancer

While less common, bladder cancer—especially transitional cell carcinoma—is a serious cause of bloody urine, mainly affecting older dogs. Cancer in the kidneys or urinary tract can also lead to blood leaking into the urine. Unlike infections or stones, these cancers often don’t respond to standard antibiotics. Signs include blood in the urine, weight loss, difficulty urinating, or recurring infections that don’t fully clear. Vets may use ultrasound or biopsy to confirm the diagnosis. Early detection offers more treatment options such as NSAIDs, chemotherapy, or referral to a specialist (RVC Oncology).

4. Blood Clotting Disorders and Poisoning

Sometimes, the bleeding isn’t caused by an infection or tumour at all. Certain poisons—like rat poison—affect the dog’s ability to form blood clots. These toxins interfere with blood clotting problems, leading to internal bleeding that shows up in the urine. Other clotting disorders may be genetic or develop from chronic infections or liver disease. Dogs may also bruise easily or bleed from the gums. The RSPCA warns that many household poisons, including anticoagulant rodenticides, can seriously affect dogs and urges immediate vet help if exposure is suspected.

5. Prostate Problems in Male Dogs

In male dogs, the prostate gland surrounds the urethra. As dogs age, the prostate can become enlarged, infected, or inflamed—conditions known as prostatitis or benign prostatic hyperplasia. These issues may press on the urinary tract, causing difficulty urinating and visible blood in the stream. You might also see your dog licking the area more than usual or passing blood even when not urinating. Treatment often includes antibiotics, hormone therapy, or castration.

6. Hormonal and Rare Conditions

Sometimes, what looks like blood in dog urine isn’t urine at all. Female dogs in heat can pass vaginal discharge that’s pink or red, which might mix with their pee. This is usually normal but can be mistaken for haematuria. Rarely, conditions like renal telangiectasia—a weakening of kidney blood vessels—can cause spontaneous bleeding. These are often found during advanced imaging or biopsy and are treated case-by-case.

Signs to Watch For

Spotting blood in your dog’s urine is only one clue. Look for a cluster of lower- or upper-urinary-tract problems:

• Frequent urination or straining to pass urine

• Strong, fishy smell or cloudy pee (think urinary tract infection)

• Dribbling in the house, licking the area, whining during pee (pain)

• Back-pain, vomiting or fever (could signal a kidney infection or kidney stones)

• Bruising, pale gums or bleeding elsewhere—possible clotting disorders from rat poison

• Weight loss or hunger drop in older dogs (raise cancer alarms)

PDSA warns UK owners that any mix of these red flags with bloody urine needs same-day vet help, even if the dog seems normal. Acting fast protects the kidneys and avoids life-threatening blockages in male or female dogs alike.

When To Call Your Vet

Call your vet immediately if:

• Your dog can’t pass urine or only dribbles—this can become fatal within hours.

• You see blood plus fever, vomiting, back pain or collapse.

• A young puppy, senior dog or older dogs with health conditions suddenly start peeing blood.

PDSA warns UK owners that an obstructed bladder is a medical emergency and urges you to contact a 24-hour clinic if your regular practice is closed. Bring a urine sample in a clean, leak-proof pot (most vets can supply one at reception) and a list of any medicines, including over-the-counter painkillers or possible rat poison access. Early lab work—urine culture, blood test and scan—lets your vet start the right treatment before damage spreads.

What Your Vet Will Do

A vet’s first job is a proper diagnosis. Expect:

1. History & exam – feeling the bladder, checking gums and blood vessels.

2. Urinalysis & urine culture – pinpoints bacterial or lower urinary tract infection; confirms antibiotic choice.

3. Blood test – measures kidney values and red-/white-blood cells.

4. Imaging – X-ray or ultrasound to find bladder stones, urinary crystals, tumours or renal telangiectasia (spontaneous widening of kidney vessels).

5. Optional cystoscopy or biopsy if cancer is suspected.

New UK trials show many straightforward UTIs clear with a 3–5-day antibiotic course, not the old 10-day default. Your vet will discuss costs up-front and may suggest spreading payments or claiming on insurance.

Treatment of Blood in Dog Urine

Your vet’s plan hinges on that cause, so the first step is always diagnostic tests: urine culture, blood work and an ultrasound or X-ray. Once the root problem is clear, treatment moves fast.

• Bacterial infection – A short course of targeted antibiotics plus pain relief is now standard in UK practice; recent studies show many UTIs clear in five days, reducing resistance risk.

• Bladder or kidney stones – Special diets dissolve some stones; others need removal. Minimally-invasive laser lithotripsy at RVC shatters most stones without open surgery, with success rates over 80 per cent in female dogs.

• Tumours – Early masses may be managed with non-steroidal anti-inflammatory drugs and chemotherapy. The RVC oncology team reports longer survival when treatment starts soon after haematuria first appears.

• Clotting disorders – If rat poison is to blame, vets give vitamin K injections and, in heavy bleeds, plasma transfusions; the RSPCA stresses that waiting at home is never safe.

• Prostate problems – Antibiotics, hormone-blocking drugs or castration ease bleeding in many male dogs.

Across all cases, plenty of fresh water, regular toilet breaks, and follow-up urine checks help stop chronic infection or stone re-growth. Acting quickly turns a frightening sight—blood in dog urine—into a treatable event, and keeps your pet’s urinary tract healthy for years.

Home Care & Prevention

A few simple habits cut the risk of dog peeing blood again:

• Fresh water and more loo breaks keep the urinary tract flushed.

• Feed a vet-approved urinary diet if your dog forms stones or crystals.

• Keep body-weight trim—obesity raises infection odds.

• Vaccinate yearly; leptospirosis is still present in UK waterways and damages kidneys.

• Lock away rat poison, ibuprofen and human chocolate; poisoning is a leading emergency call to RSPCA lines.

• Neuter males prone to prostate swellings and female dogs if owners don’t plan to breed—to avoid hormonal bleeding confusions.

FAQs

Is blood in dog urine an emergency?

Yes. Any blood in the urine—even a single pink patch—warrants a vet call the same day to rule out blockages or toxins.

Why is my dog peeing blood but acting normal?

Early bacterial infection, tiny stones or mild trauma can leak blood before pain starts. Don’t wait; small problems escalate fast.

Can blood in urine go away on its own?

Rarely. Some self-limiting bruises clear, but most causes—urinary tract infection, stones, tumours—need drugs or surgery.

How to treat a dog with blood in urine?

Only a vet can decide. Expect urine culture, maybe X-ray, and then a tailored plan—antibiotics, stone-dissolving diet, surgery or chemo depending on the underlying cause. Skipping vet care risks kidney failure or sepsis.

Conclusion

Blood in dog urine is always a sign that something inside your pet’s urinary system isn’t right. Act fast, follow your vet’s advice, and you’ll give your dog the best chance of a full recovery—and many more happy, worry-free walks.