A dog with a urinary tract infection will typically squat frequently and produce only small amounts of urine, sometimes with visible blood or a noticeably foul smell. You might also notice your dog licking their genital area more than usual, having accidents indoors despite being housetrained, or whimpering while trying to pee. These signs can appear suddenly and tend to worsen over a few days without treatment.
Behavioral Signs You’ll Notice First
The earliest and most obvious sign is a change in your dog’s bathroom habits. A dog with a UTI will squat or lift their leg repeatedly, straining to urinate but only passing small dribbles each time. They may ask to go outside far more frequently than normal, or they may start having accidents in the house even though they’ve been reliably housetrained for years.
Between bathroom trips, you’ll likely see your dog excessively licking their genital area. This licking can become so persistent that it causes copper-colored staining on the fur around the vulva or penis, a discoloration caused by saliva. The area may also look swollen or inflamed. Some dogs show signs of pain during urination, crying out or hesitating before they go, then rushing to finish.
What the Urine Looks Like
Healthy dog urine is pale to medium yellow and relatively clear. During a UTI, the urine often turns cloudy and may take on a darker color. The most alarming change is blood: you might see a pinkish or reddish tint, or even drops of frank blood at the end of urination. On light-colored surfaces like snow, concrete, or puppy pads, even small amounts of blood are easy to spot.
The smell changes too. UTI urine has a strong, foul odor that’s distinctly different from normal urine. If you notice a sharp, unusually pungent smell when your dog pees, that’s a reliable early indicator something is off.
Why Female Dogs Get UTIs More Often
Female dogs are significantly more prone to UTIs than males. The reason is straightforward anatomy: females have a shorter urethra, which gives bacteria a shorter path to travel from the outside environment up into the bladder. Bacteria from the fecal and perineal area colonize the urethral opening and migrate upward, and a shorter distance means less opportunity for the body’s natural defenses to stop them.
Changes in the vaginal microbiome can also play a role, making it easier for harmful bacteria to establish themselves. Male dogs aren’t immune to UTIs, but their longer urethra provides more of a natural barrier. When males do develop UTIs, the infection is more likely to involve the prostate, which can complicate treatment.
How Vets Confirm a UTI
Your vet will need a urine sample. The gold standard is a sample collected directly from the bladder using a small needle through the abdomen (it sounds dramatic, but most dogs tolerate it well and it takes seconds). This method avoids contamination from bacteria on the skin or in the lower urinary tract, giving the cleanest possible result.
If that’s not feasible, a free-catch sample, one you collect midstream while your dog is urinating, is also useful. Research comparing the two methods shows strong agreement between them for key diagnostic markers, so a clean free-catch sample still provides reliable information. Your vet may give you a sterile container and ask you to bring one from home.
The urinalysis looks for white blood cells (more than 5 per microscope field suggests infection), bacteria, protein, and changes in urine pH. Infection-causing bacteria can make urine more alkaline than normal. A urine culture identifies the specific bacteria involved and which antibiotics will work against it.
What Happens if a UTI Goes Untreated
A simple UTI that clears up with treatment is uncomfortable but not dangerous. Left untreated, though, the infection can move beyond the bladder. Bacteria can travel up to the kidneys, causing a kidney infection that brings more serious symptoms like fever, vomiting, lethargy, and loss of appetite.
There’s another complication that’s less obvious but common: bladder stones. Certain bacteria, particularly Staphylococcus and Proteus species, produce an enzyme that breaks down urea in the urine into ammonia. This raises the urine’s pH, creating conditions where minerals crystallize and clump together into stones called struvite uroliths. These stones can grow large enough for a vet to feel through the abdomen, and they cause symptoms that look identical to a UTI: bloody urine, straining, frequent urination.
The tricky part is that bacteria can embed themselves inside these stones, shielded from antibiotics. Even after the urine tests clean, bacteria hiding within the stone can re-emerge and restart the infection cycle. Small stones under 3 millimeters may not even show up on X-rays or ultrasound, making them easy to miss. This is one reason recurring UTIs always warrant further investigation beyond a basic urinalysis.
How UTIs Look Different From Bladder Stones
The symptoms of a simple UTI and bladder stones overlap almost completely: frequent urination, blood in urine, straining, and discomfort. The key difference is what happens when stones cause a blockage. If a stone lodges in the urethra and blocks urine flow, the situation escalates quickly. A dog with a urinary obstruction will vomit, become lethargic, show signs of abdominal pain, and become dehydrated. This is a veterinary emergency that can lead to bladder rupture if not treated promptly.
Because the symptoms look so similar, vets typically recommend imaging (X-rays or ultrasound) alongside urinalysis when a UTI doesn’t respond to treatment as expected, or when infections keep coming back.
Treatment and Recovery Timeline
A straightforward UTI is treated with a short course of antibiotics, typically 3 to 5 days for a simple bladder infection. Your dog should start showing improvement within the first day or two of treatment, with symptoms largely resolved by the time the course is finished.
Complicated or recurring infections require longer treatment. UTIs in male dogs often need an extended course because the prostate may be involved, and antibiotics take longer to penetrate prostate tissue effectively. Your vet will likely recommend a follow-up urine culture after treatment ends to confirm the bacteria are truly gone.
Do Cranberry Supplements Help?
Cranberry supplements are widely marketed for dogs, but the evidence behind them is weak. A systematic review of cranberry supplementation for urinary infections in dogs and cats found no studies reporting statistically significant benefits for either prevention or treatment. The International Society for Companion Animal Infectious Diseases stated in its 2019 guidelines that there is insufficient evidence to recommend cranberry extract products for preventing or treating bladder infections in dogs.
Because these products are sold as nutraceuticals rather than pharmaceuticals, manufacturers aren’t required to prove they work. There’s no established effective dose, and product quality varies. Cranberry supplements are unlikely to harm your dog, but they shouldn’t be relied on as a substitute for veterinary care when symptoms are present.