# Blood in Urine or Stool in Senior Dogs Blood in urine in senior dogs deserves a closer look than the same sign in a young dog. Older dogs are more likely to have cancer, chronic kidney disease, or a urinary tract infection behind the bleeding, and early stages of these conditions often cause no other signs [1]. Blood in stool in older dogs carries similar weight because it can point to problems in the intestines, anal glands, or internal organs. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - Any blood in urine or stool in a dog over 7 years old should be checked by a veterinarian, even if your dog seems fine otherwise. - Blood can be visible (pink, red, or brown urine) or invisible (occult blood), which only a urine test can detect. - Common causes include urinary tract infection, bladder or kidney stones, and tumors of the bladder, kidney, or prostate. - Chronic kidney disease is staged from I to IV, and Stage I is the best time to treat, but most dogs are not diagnosed until later stages because there are no signs [1]. - Bring a fresh urine sample and a stool sample to the visit if you can, and note how much your dog drinks, urinates, and eats [2]. ## What Blood in Urine or Stool Looks Like in an Older Dog Blood in urine can look like many things. You might see pink or red streaks in the urine, a brownish tint, or blood droplets on the grass or pad. Sometimes the urine looks normal but a test strip shows blood. That is called occult blood, and it is common in older dogs with low-grade bleeding from the bladder or kidneys. Blood in stool can be bright red and coating the surface, which usually means bleeding near the end of the digestive tract. It can also be dark, tarry, and black, which points to bleeding higher up. Both forms matter in a senior dog. Normal urine in dogs ranges from pale yellow to amber. Normal stool is firm and brown. Any red, pink, brown, or black discoloration is worth a call to your veterinarian. ## Main Causes of Blood in Urine in Senior Dogs The urinary system includes the kidneys, ureters, bladder, and urethra [3]. Bleeding can come from any part of this tract, and the cause changes with age. | Cause | Typical clues | How urgent | |---|---|---| | Urinary tract infection | Frequent small urinations, straining, accidents in the house, strong odor | See a vet within 24 to 48 hours | | Bladder or kidney stones | Straining, dribbling, pain, blood at the end of urination | Same-day visit, emergency if your dog cannot urinate | | Bladder or kidney cancer | Blood that comes and goes, weight loss, straining, no response to antibiotics | Same-day to next-day visit | | Chronic kidney disease | Increased drinking and urination, weight loss, poor appetite | See a vet within a few days | | Idiopathic renal hematuria | Ongoing visible blood from one kidney, no other cause found on imaging | Routine to urgent depending on blood loss | | Prostate disease in male dogs | Straining to defecate, blood at the tip of the penis, hind limb stiffness | See a vet within a few days | | Bleeding disorders or toxin exposure | Bruising, nosebleeds, gum bleeding, recent rodenticide exposure | Emergency now | Stones and infection often occur together. In one study of working dogs, dogs with urolithiasis showed abdominal pain, difficult urination, blood in urine, and urinary retention, along with lower red blood cell counts and higher white cell counts [4]. Stone formation is not only about urine chemistry. Recent work shows that immune cells release web-like structures that promote crystal clumping and stone growth in dogs [5]. Idiopathic renal hematuria is a diagnosis made after other causes are ruled out. It has been treated with sclerotherapy in some dogs, and one report described complete resolution of bleeding after a 6-week course of oral tranexamic acid [6]. These are specialist decisions, not home treatments. ## Main Causes of Blood in Stool in Older Dogs Blood in stool in older dogs often comes from the large intestine, the anal area, or the stomach and small intestine. Common causes include colitis, intestinal parasites, anal sac disease, benign growths, and intestinal tumors. Bleeding can also come from swallowed blood, stomach ulcers, or a bleeding disorder. If the stool is bright red, the problem is usually in the lower tract. If it is black and tarry, the bleeding is likely higher up and has been digested. Black stool is more concerning because it can mean a large volume of blood loss. Some senior dogs have both urinary and stool changes. If your older dog is also having accidents in the house, that can reflect cognitive decline, urinary tract disease, or both. The relationship between soiling behavior, urinalysis abnormalities, and cognitive decline in aging dogs is an active area of study, and one cohort found hematuria in a portion of urine samples from aging dogs [7]. You can read more about this pattern in [Older Dog Peeing In House](/knowledge/veterinary-medicine/symptom-guides/older-dog-peeing-in-house) and [Old Dog Peeing In House](/knowledge/veterinary-medicine/symptom-guides/old-dog-peeing-in-house). ## Red Flags That Mean Emergency Care Now Call an emergency clinic right away if you see any of these: - Your dog is straining to urinate and nothing comes out, or only drops come out. This can mean a blockage, which is life threatening, especially in male dogs. - Your dog is vomiting, weak, collapsed, or breathing fast. - The bleeding is heavy or continuous. - Your dog's gums are pale or white. - You see bruising on the belly or gums, or bleeding from the nose. - You know or suspect your dog ate rat poison. - Your dog has a distended, painful belly. For non-emergency bleeding, call your regular veterinarian the same day. Early testing is how senior dogs get the best shot at treatment. Chronic kidney disease is classified into four stages, and Stage I offers the greatest chance of success, but it is rarely caught because there are no signs [1]. ## Safe Things You Can Do at Home While You Wait You cannot treat bleeding at home, but you can protect your dog and gather useful information. - Do not give human pain relievers. Many are toxic to dogs. - Do not give antibiotics left over from another pet. - Collect a fresh urine sample in a clean container if you can catch it. Free-catch samples are used in research and clinical settings [7]. - Collect a stool sample in a sealed bag. - Write down how much your dog drinks, how often it urinates, and whether it strains. - Note any diet changes, new treats, or new medications [2]. - Keep your dog hydrated and offer normal meals unless your vet says otherwise. - If your dog is bleeding heavily or cannot urinate, skip home care and go to the clinic. If you want more detail on what blood in stool can mean, see [Blood in dog stool causes urgency and veterinary evaluation](/knowledge/veterinary-medicine/emergency-care/blood-in-dog-stool) and [Dog Blood in Stool: Home Care and When to Call the Vet](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-blood-in-stool-home-care). ## What Your Veterinarian Will Check and Test Your veterinarian will start with a full history and physical exam. Expect questions about water intake, urination frequency, urine volume, appetite, weight change, and any medications your dog takes [2]. The exam includes feeling the belly, checking the prostate in male dogs, and checking the gums and lymph nodes. Testing usually includes: - Urinalysis. This checks for blood, protein, bacteria, crystals, and urine concentration. Protein in the urine is common in aging dogs and can be an early sign of kidney injury [7][8]. - Urine culture. This confirms infection and guides antibiotic choice. - Blood work. This checks kidney values, electrolytes, and blood cell counts. - Imaging. X-rays and ultrasound look for stones, tumors, and kidney changes. Ultrasound can show changes in kidney texture even when blood work is normal [8]. - Blood pressure. High blood pressure is common with kidney disease and can worsen bleeding. - Stool testing. This checks for parasites and hidden blood. - Referral testing. Cystoscopy or contrast imaging may be needed when the source of bleeding is not clear. A newer approach uses early markers such as the urine protein-to-creatinine ratio and urinary enzyme ratios to detect kidney injury before standard blood work changes. In one study of non-azotemic geriatric dogs, these markers differed significantly from young dogs, and ultrasound showed kidney changes in some cases [8]. This matters because catching kidney disease earlier gives you more treatment options. If your dog has blood in urine, your vet may also consider testing for occult blood specifically. Occult blood in urine in dogs means bleeding that is not visible to the eye. It is found on a urine dipstick and always needs follow-up. ## Prevention and Monitoring for Senior Dogs You cannot prevent every cause of bleeding, but you can lower risk and catch problems earlier. - Schedule twice-yearly wellness visits for dogs over 7 years old. Ask for a urinalysis and blood work each time. - Watch water intake. A sudden increase in drinking is one of the earliest signs of kidney disease [1]. - Keep your dog at a healthy weight. Obesity raises the risk of many diseases. - Feed a balanced diet and avoid table scraps that can cause stomach upset. - Keep fresh water available at all times. - Monitor for straining, dribbling, accidents, and changes in stool color. - Ask your vet about prostate checks for male dogs. - Keep all medications, including human drugs, out of reach. If your dog has had stones before, ask about follow-up imaging and urine testing. Stones are highly recurrent, and immune factors appear to play a role in how they grow [5]. ## Limitations and When to Contact a Veterinarian This article cannot tell you what is causing your dog's bleeding. Only a veterinarian who examines your dog and runs tests can do that. Contact your veterinarian the same day if you see blood in urine or stool, if your dog is straining, or if your dog has accidents in the house. Go to an emergency clinic now if your dog cannot urinate, is vomiting, is weak or collapsed, has pale gums, or has heavy bleeding. A routine visit is fine for a small amount of blood that comes and goes in a dog that is eating, drinking, and acting normally, but do not wait more than a few days. ## Frequently Asked Questions ### Is blood in urine always a sign of cancer in older dogs? No. Infection, stones, and kidney disease are common causes. Cancer is more likely in senior dogs, which is why testing matters. Your veterinarian can narrow the cause with urine tests, blood work, and imaging. ### Can blood in urine go away on its own? Sometimes the visible blood stops, but the underlying cause usually remains. Occult blood can persist even when urine looks normal. A vet visit is still needed to find the source. ### Should I bring a urine sample to the appointment? Yes, if you can collect one cleanly. A fresh sample helps your vet run a urinalysis right away. If you cannot get one, your vet can collect a sample in the clinic. ### Does blood in stool mean my dog has parasites? Not always. Parasites are one cause, but colitis, anal sac disease, growths, and tumors also cause bleeding. Stool testing helps sort this out. ### How often should a senior dog have urine testing? Twice a year is a reasonable schedule for most dogs over 7 years old. Dogs with kidney disease, stones, or a history of urinary problems may need testing more often. Ask your vet what schedule fits your dog. ## Related Articles - [Dog Blood in Urine: Causes and Emergency Steps](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-blood-in-urine-causes-emergency-steps) - [Blood in dog stool causes urgency and veterinary evaluation](/knowledge/veterinary-medicine/emergency-care/blood-in-dog-stool) - [Older Dog Peeing In House](/knowledge/veterinary-medicine/symptom-guides/older-dog-peeing-in-house) - [Dog Blood in Stool: Home Care and When to Call the Vet](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-blood-in-stool-home-care) - [Old Dog Peeing In House](/knowledge/veterinary-medicine/symptom-guides/old-dog-peeing-in-house) - [Dog Blood in Stool but Acting Normal: What Does It Mean?](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-blood-in-stool-acting-normal) - [Blood in Dog Urine or Stool: Treatment Options](/knowledge/veterinary-medicine/digestive-and-urinary-care/blood-in-urine-stool-dogs-treatment) - [Red Dog Urine: Causes, Blood in Pee, and When to Call the Vet](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-urine-red-causes) - [Blood Clots in Dog Poop: Causes and What to Do](/knowledge/veterinary-medicine/digestive-and-urinary-care/blood-clots-in-dog-poop) ## References 1. [Noninfectious Diseases of the Urinary System in Dogs - Dog Owners](https://www.merckvetmanual.com/dog-owners/kidney-and-urinary-tract-disorders-of-dogs/noninfectious-diseases-of-the-urinary-system-in-dogs). Merck Veterinary Manual. 2. [Detecting Disorders of the Kidneys and Urinary Tract in Dogs - Dog Owners](https://www.merckvetmanual.com/dog-owners/kidney-and-urinary-tract-disorders-of-dogs/detecting-disorders-of-the-kidneys-and-urinary-tract-in-dogs). Merck Veterinary Manual. 3. [The Urinary System of Dogs - Dog Owners](https://www.merckvetmanual.com/dog-owners/kidney-and-urinary-tract-disorders-of-dogs/the-urinary-system-of-dogs). Merck Veterinary Manual. 4. [Comprehensive diagnostic evaluation of urolithiasis and cystitis in K9 dogs in Iraq: Clinical, laboratory, and imaging correlates](https://pubmed.ncbi.nlm.nih.gov/41630760/). Open veterinary journal, 2025. 5. [Neutrophil Extracellular Traps Promote Urolithiasis Formation in Dogs: A Preliminary Study](https://pubmed.ncbi.nlm.nih.gov/41897919/). Animals : an open access journal from MDPI, 2026. 6. [Tranexamic acid resolved idiopathic renal hematuria in a dog](https://pubmed.ncbi.nlm.nih.gov/42699376/). The Canadian veterinary journal = La revue veterinaire canadienne, 2026. 7. [The relationship between urinalysis abnormalities, soiling behavior, and cognitive decline in aging dogs](https://pubmed.ncbi.nlm.nih.gov/42806282/). Journal of veterinary internal medicine, 2026. 8. [Early renal changes in non-azotemic geriatric dogs detected by clinical biomarkers and ultrasonography](https://pubmed.ncbi.nlm.nih.gov/41400730/). Veterinary research communications, 2025. ## Further Reading - [American Veterinary Medical Association: First Aid Tips for Pet Owners](https://www.avma.org/resources-tools/pet-owners/emergencycare/first-aid-tips-pet-owners) - [Merck Veterinary Manual: Dog Owners](https://www.merckvetmanual.com/dog-owners) - [Cornell Richard P. Riney Canine Health Center: Canine Health Information](https://www.vet.cornell.edu/departments-centers-and-institutes/riney-canine-health-center/canine-health-information)