Green urine in dogs is not normal and usually signals that something is going on internally, whether it’s a pigment-producing bacterial infection, a problem with how your dog’s body processes old red blood cells, or a liver or gallbladder issue that’s pushing bile pigments into the urine. While the shade can range from faintly green-tinged to a striking emerald, any clearly green urine warrants a veterinary visit.
How Urine Turns Green
To understand green urine, it helps to know what makes urine yellow in the first place. When your dog’s body recycles old red blood cells, it produces a green substance called biliverdin. An enzyme then converts that green biliverdin into yellow bilirubin, which eventually gets processed by the liver and excreted. The yellow color of normal urine comes from this pathway working correctly.
When something disrupts this process, biliverdin can build up instead of being converted. That green pigment ends up in the bloodstream and gets filtered into the urine, producing a visibly green color. The disruption can happen at several points: the enzyme itself may not work properly, the liver may be overwhelmed, or red blood cells may be breaking down faster than the body can handle.
A Rare Genetic Enzyme Defect
Researchers at the University of Minnesota identified a genetic condition caused by defects in a gene called BLVRA. This gene provides instructions for making biliverdin reductase A, the enzyme responsible for converting green biliverdin into yellow bilirubin. When the enzyme doesn’t function properly, biliverdin accumulates in the body and produces strikingly green urine. This is a rare condition, but it’s one of the most dramatic and well-documented causes of truly green urine in dogs.
Dogs with this defect may appear otherwise healthy, since the buildup of biliverdin alone doesn’t always cause obvious illness right away. But the condition does indicate that red blood cell recycling isn’t working as it should, which can have downstream effects over time.
Bacterial Urinary Tract Infections
A more common explanation is a urinary tract infection caused by Pseudomonas bacteria. Unlike most bacteria that cause UTIs, Pseudomonas species produce their own pigments called pyocyanin and pyoverdine. These pigments are blue-green in color, and when they mix with urine, the result can look distinctly green.
If a Pseudomonas infection is the cause, you’ll likely notice other signs of a UTI as well: frequent urination, straining to pee, accidents in the house, or urine that smells unusually strong. Your vet can confirm this with a urine culture, which identifies the specific bacteria involved. This matters because Pseudomonas infections can be more resistant to standard antibiotics than typical UTI-causing bacteria, so targeted treatment is important.
Liver and Gallbladder Problems
The liver plays a central role in processing bilirubin and excreting it through bile. When the liver is diseased or the bile ducts are blocked, bile pigments can back up into the bloodstream and spill into the urine. Depending on the mix of pigments, this can produce urine ranging from dark amber to greenish.
One condition worth knowing about is gallbladder mucocele, where thick, mucus-laden bile accumulates in the gallbladder. This material can range from pale yellow to dark green, and it can obstruct the bile ducts. When that happens, bilirubin levels in the blood rise (a condition called hyperbilirubinemia), and your dog may develop jaundice, where the skin, gums, and whites of the eyes take on a yellow tint. In some cases, the obstruction causes acute illness that requires emergency surgery.
Other liver conditions, including infections, toxin exposure, and certain cancers, can similarly interfere with bile processing and alter urine color. Dogs with liver problems often show additional symptoms like vomiting, loss of appetite, lethargy, or a swollen abdomen.
Rapid Red Blood Cell Destruction
Any condition that causes red blood cells to break down faster than normal can overwhelm the biliverdin-to-bilirubin conversion pathway. Immune-mediated hemolytic anemia (IMHA) is one of the more serious examples. In IMHA, the dog’s immune system mistakenly attacks its own red blood cells, destroying them in large numbers. The flood of breakdown products can exceed the body’s processing capacity, and excess biliverdin may end up in the urine.
Dogs with IMHA are usually visibly unwell. You might notice pale or yellow gums, rapid breathing, weakness, dark or discolored urine, and a sudden drop in energy. This is a medical emergency that requires immediate treatment, typically involving hospitalization and immune-suppressing medications.
What About Diet and Supplements?
Before assuming the worst, consider whether your dog recently ate something unusual. Certain artificial dyes in treats or chew toys can temporarily tint urine. Some supplements and medications also change urine color. If the green color appeared right after introducing a new food, treat, or supplement, that’s worth mentioning to your vet, as it could be the simplest explanation.
That said, diet-related green urine is far less common in dogs than the medical causes listed above. If the color persists beyond a single urination or your dog shows any other symptoms, don’t chalk it up to food.
What Your Vet Will Check
A standard urinalysis is the first step. This test measures bilirubin levels in the urine, checks for bacteria, and evaluates other markers of kidney and liver function. It’s worth noting that dogs naturally have a lower threshold for bilirubin in their urine compared to other animals, and male dogs in particular can show trace amounts of bilirubin in concentrated urine without it being a problem. But green-colored urine goes well beyond trace levels.
Depending on what the urinalysis shows, your vet may also run blood work to assess liver function and red blood cell counts, perform a urine culture to identify specific bacteria, or use ultrasound to look at the liver and gallbladder. If gallbladder mucocele is suspected, imaging is especially important because some cases progress to rupture, which is life-threatening.
Warning Signs That Need Urgent Attention
Green urine on its own is unusual enough to schedule a vet appointment. But certain accompanying symptoms mean you should go sooner rather than later:
- Yellow-tinged gums, skin, or eyes (jaundice), which points to liver dysfunction or rapid red blood cell breakdown
- Pale or white gums, suggesting severe anemia
- Vomiting, diarrhea, or refusal to eat, especially if sudden
- Extreme lethargy or collapse
- Rapid or labored breathing
- A swollen or painful abdomen
If your dog has green urine along with any of these signs, treat it as urgent. Conditions like IMHA and bile duct obstruction can deteriorate quickly, and early intervention makes a significant difference in outcomes.