Blood in Dog Urine: 6 Common Causes

If you’ve noticed blood in your dog’s urine, you’re probably feeling a bit concerned – and rightly so. Blood in dog urine can be a scary thing to see. 

There are several possible causes, and it’s important for your dog to see a veterinarian to obtain a diagnosis and treatment. 

Let’s look at the six most common causes for blood in a dog’s urine and what other symptoms you might see if your dog has one of these conditions.

Blood in Dog Urine: What it Looks Like

Blood in a dog’s urine can have a variable appearance depending on the volume of blood present. 

Sometimes, the urine is slightly pink-tinged because a very small volume of blood is present. Other times, the urine may appear obviously red from a large volume of blood present. You may also see urine with red blood clots in it or specks of red blood. 

Some pet owners may spot blood in their dog’s urine when their dog urinates outside, but if the volume of blood in the urine is small, this may be tough to see. Other owners only notice blood in the urine when they see the urine against a light-colored background, such as when the dog urinates on snow or when wiping up urine with a paper towel.

What Causes Blood in a Dog’s Urine?

There are several possible causes for blood in the urine. Because many of these causes can have similar symptoms, it’s important not to try to diagnose your dog at home. If your dog has bloody urine, see your veterinarian right away for an appropriate diagnosis and treatment. 

Possible causes for blood in the urine include:

Urinary Tract Infection

Possibly the most common cause for blood in the urine is a urinary tract infection. Urinary tract infections occur when bacteria from the genitalia and urethra penetrate a dog’s bladder. In addition to blood in the urine, other symptoms may include pain, frequent urination, urinating small volumes, and inappropriate urination. Urinary tract infections are more common in female dogs than in males. 

Kidney Infection

A kidney infection – also called pyelonephritis – is a bacterial infection of one or both kidneys. It commonly occurs when an infection from the lower urinary tract – the bladder and urethra – ascends to the kidney(s) via the ureters. Some dogs with kidney infection are asymptomatic, while others have upper urinary tract signs including increased drinking, increased urination, kidney pain, vomiting, lethargy, loss of appetite, fever, and blood in the urine. 

Urolithiasis (Urinary Stones)

Stones in the urinary tract – known medically as urolithiasis – can cause blood in the urine due to the resulting inflammation and trauma to the surrounding tissues. Stones can be found in the upper urinary tract, such as in the kidney or ureter, or in the lower urinary tract, such as in the bladder or urethra. The majority of stones occur in the lower urinary tract. Other symptoms of urinary stones include painful urination, frequent urination, and urinary incontinence. 

Tumors

Tumors of the lower urinary tract may lead to blood in the urine as well as other symptoms such as straining to urinate, more frequent urination, painful urination, and incontinence. Dogs with tumors of the lower urinary tract may also strain to defecate due to the tumor pressing against the rectal wall. Tumors of the bladder or urethra may lead to urinary tract obstruction, resulting in unproductive straining, pain, lethargy, and systemic illness.

Prostatic Disease

In unneutered male dogs, diseases of the prostate such as Benign Prostatic Hypertrophy and prostatitis (inflammation of the prostate) can cause blood in the urine. These conditions are common in intact (unneutered) male dogs and uncommon in neutered males. Other symptoms associated with prostate disease include straining to defecate, increased urination, straining to urinate, urinary incontinence, and bleeding from the penis.

Bleeding Disorders

A less common, but possible, cause of blood in dog urine is a bleeding disorder. Bleeding disorders can be inherited or can be acquired secondary to other conditions. One example of an acquired bleeding disorder is bleeding that occurs due to rodenticide toxicity, which can result in blood in the urine. Typically, blood in the urine is not the first or only symptom of a bleeding disorder. Other symptoms may include pale gums, weakness, bruising, bleeding from the nose, coughing, or exercise intolerance. 

Other Symptoms to Watch For

Any time you see blood in your dog’s urine, it warrants a trip to the veterinarian. Be sure to note any other symptoms your dog may be experiencing, such as straining to urinate, painful urination, frequent urination, accidents in the house, or any other changes in health or behavior. Make sure to tell your veterinarian about these symptoms at your visit, as they can help your veterinarian diagnose the cause of your dog’s changes in urination. 

Your veterinarian will likely also ask you about any changes in your dog’s eating and drinking habits, energy level, and defecation habits. This history is an important part of your pet’s medical workup, so be sure to give your veterinarian as much detail as you can.

Diagnosing the Cause of a Dog Peeing Blood

To diagnose the cause of the blood in your dog’s urine, your veterinarian may recommend some or all of the following tests:

Physical Examination. Your veterinarian will perform a comprehensive head-to-tail physical examination, including palpating your dog’s abdomen and examining your dog’s genitalia. The physical examination may also include a rectal examination, which allows the veterinarian to palpate the urethra and examine the prostate in male dogs.

Urinalysis. Your veterinarian will likely request a urine sample for analysis which can be used to identify blood in the urine as well as other changes such as bacteria, crystals, and casts in the urine. 

Radiographs (X-Rays). Your veterinarian may recommend radiographs (X-rays) of your pet’s abdomen to evaluate the urinary tract. Radiographs can help diagnose abnormalities such as stones and certain types of prostatic disease, as well as identify changes associated with other systemic illnesses.

Ultrasound. Your veterinarian may recommend ultrasound imaging of your pet’s urinary tract to evaluate structures such as the bladder, kidneys, and prostate. Ultrasound can be used to diagnose certain diseases and may also be used to collect urine samples via a special method called cystocentesis.

Blood in Dog Urine Treatment

The treatment for blood in your dog’s urine depends on the underlying cause. Some causes of blood in the urine, such as urinary tract infections or kidney infections, are treated with prescription medications from your veterinarian. Other causes of blood in the urine, such as bladder stones, are treated with surgery to remove the stones. Your veterinarian will determine the best course of treatment for your dog.

You should not attempt any home remedies. There are no effective home remedies that will get rid of blood in your dog’s urine. It is important not to delay seeking veterinary care for blood in the urine, as many causes of this issue can be serious and can progress in severity if left untreated. You should never attempt to treat your dog with home remedies or over-the-counter treatments unless directed to do so by your veterinarian.

How to Prevent Blood in Dog Urine

Prostatic disease can be prevented by having your dog neutered. In dogs predisposed to developing bladder stones, a prescription veterinary diet may be used to prevent the recurrence of bladder stones following initial treatment. In general, other causes of blood in the urine cannot be prevented.