Causes of Blood in Dog Urine

Photo by: Bigstockphoto
Photo by: Bigstockphoto

It’s any pet owner’s worst nightmare, seeing blood in their pooch’s urine. This condition is called hematuria. Familial hematuria—a condition in which bloody urine runs in certain animal families—is common in younger dogs. In older dogs, bloody urine may indicate cancer. Female dogs afflicted with urinary tract infection could also lead to blood in urine. Female dogs with urinary tract infection have a higher chance of having bloody urine than male dogs.

It can be difficult to determine what’s causing bloody urine in dogs on your own. As such, we recommend taking your dog to your local vet for proper diagnosis.

Possible Causes for Bloody Urine in Dogs

Depending on your dog’s health and its hereditary inclination to develop certain diseases, blood in dog urine could be caused by:

Internal Injury

Bloody urine could also indicate severe trauma in the dog’s body. Maybe Fido was accidentally left out in the yard and had an injury. To be on the safe side, take your dog to your vet and have blood work done to determine if the bloody urine is caused by an infection or internal bleeding.


While a poisoned dog will exhibit other symptoms, blood in urine is the most common red flag of poisoning. If your dog has blood in his urine and is vomiting and drooling profusely, rush your pooch to the nearest vet immediately. In such cases, every second counts. Early treatment could save your dog from possible death due to poisoning.

Estrus Cycle in Female Dogs

An intact female dog will bleed during her heat cycle and—in some cases—traces of blood are present in its urine. As early as six months old, a female dog will go in heat and will result in vaginal swelling and bleeding in the first week. Bleeding will stop for a week or so when it’s ready to mate.


Bloody urine could indicate either a minor or a serious infection in dogs. Kidney disease, bladder infection, and even an irritated, inflamed urethra or prostate could lead to bloody urine. In most times, these kinds of infections are treatable with antibiotics and a special diet.

Kidney or Bladder Stones

Passing kidney stones or bladder stones can cause blood to be flushed out through urine. Female dogs, in particular, have an easier time passing stones than male dogs but both male and female dogs will be in pain during the process. If you suspect that your pooch is passing stones, it’s important to call your vet and get prescribed medicine to break out the stones. Surgery is also an option but only for very severe cases.


Cancerous and non-cancerous tumors can also cause dogs to have bloody urine. Cancer is actually one of the main reasons for bloody urine so it’s important to have your dog checked for such disease. If your dog does indeed have tumors, get your vet to run some tests to determine whether the tumor is malignant or not.

Finally, you can discuss the next steps for treating the tumors with your vet. Usually the treatment will depend on your dog’s age and the progression of the tumor.