# Why Does My Dog Smell Like Fish? Urine and Skin Causes A fishy smell from your dog usually comes from one of three places: the anal glands, the urinary tract, or the skin and ears. Each has its own pattern, and the pattern is what tells you whether this is a grooming issue or a medical one. If you have ever asked yourself why does my dog smell like fish, the answer almost always starts with where the odor is coming from. This article is educational and is not a substitute for veterinary diagnosis or treatment. ## Quick Answer - A sudden fishy smell near the rear end is most often anal gland fluid, which is normal in small amounts but abnormal if it happens often. - Fishy urine points toward a urinary tract infection or another urinary problem, and this needs a vet visit, not a bath. - A fishy or yeasty smell from the skin, ears, or paws usually means a skin infection or allergy flare. - Puppies can smell fishy for the same reasons adult dogs do, plus puppy-specific issues like stool stuck in the coat or immature anal glands. - Never treat a suspected infection at home with leftover antibiotics or human medicine. Your vet needs to identify the problem first. ## What the Smell Looks Like and What Is Normal Dogs are not supposed to smell like perfume, but they should not smell like fish either. A healthy dog has a mild, doggy odor that you notice mostly when you are close. Normal anal gland fluid is a thin, brownish or grayish liquid with a sharp, fishy or metallic smell. It is released in tiny amounts when your dog poops or when they are startled. You might catch a whiff once in a while and then it fades. What is not normal is a strong fishy smell that lingers for hours or days, a smell that keeps coming back, or a smell paired with licking, scooting, or straining. Those patterns point to a problem that needs attention. ## Why Does My Dog Smell Like Fish? The Main Causes Most fishy odors fall into a few categories. The table below gives you a quick way to sort out what you are dealing with. | Cause | Typical clues | How urgent | |---|---|---| | Anal gland problems | Scooting, licking the rear, fishy smell near the tail, straining to poop | Routine visit, sooner if painful or swollen | | Urinary tract infection | Fishy urine, frequent peeing, accidents in the house, blood in urine, straining to pee | Same-day visit | | Kidney or bladder stones | Fishy urine, dribbling, pain, blood in urine | Same-day visit | | Skin infection or allergy | Fishy or yeasty smell on the body, redness, itching, hair loss | Routine visit | | Ear infection | Fishy smell from the ears, head shaking, scratching at ears | Routine visit, sooner if the ear is swollen or painful | | Puppy-specific causes | Fishy smell in a young dog, stool in the coat, immature anal glands | Routine visit if it persists | | Diet or grooming residue | Smell after eating certain foods or after swimming | Home care | ### Anal Gland Problems The anal glands are two small sacs on either side of your dog's anus. They produce a fluid that smells fishy by design. When they empty normally, you rarely notice. When they do not empty well, the fluid builds up and the smell gets stronger. Signs include scooting across the floor, licking or biting at the rear end, a fishy smell right at the tail base, and straining or crying when pooping. Some dogs release a burst of fishy fluid when they are scared or excited. Small breeds and dogs with soft stools seem to have more trouble with anal glands. Soft stool does not press on the glands enough to empty them. If your dog has repeated anal gland issues, your vet may look for an underlying cause like allergies or a low-fiber diet. ### Urinary Tract Infections and Fishy Urine If the fishy smell is coming from your dog's urine, that is a different story. A fishy or strong urine smell is a common sign of a urinary tract infection. Urinary tract infections are common in dogs. In one study of dogs with signs of urinary tract infection, 37.7% had bacterial growth on culture [1]. The most common bacteria found was Escherichia coli, which caused 42.6% of dog infections in that study [1]. Other bacteria like Staphylococcus, Enterococcus, and Proteus also show up [1]. Less common bacteria can also cause infections. One report described a dog with a urinary tract infection caused by Pluralibacter gergoviae, a bacterium usually found in the environment [2]. This is rare, but it shows why a urine culture matters. Your vet needs to know which bacteria is present to pick the right antibiotic. Some urinary infections are more serious than others. A kidney infection (pyelonephritis) causes higher levels of inflammation than a simple bladder infection. In one study, dogs with bladder infections had a median C-reactive protein of 1.04 mg/dL, while dogs with kidney infections had much higher levels [3]. This is why your vet may run blood work along with a urine test. ### Skin and Ear Infections A fishy smell from your dog's body or ears is often a sign of a skin infection. Yeast and bacteria that live on the skin can overgrow when your dog has allergies, a weakened immune system, or skin folds that trap moisture. Signs include redness, itching, greasy or flaky skin, hair loss, and a musty or fishy odor. Dogs with allergies often have both itchy skin and repeated skin infections. If your dog is itchy and smells fishy, the two problems are likely connected. You can read more about itching in our guide on [why is my dog so itchy](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-dog-so-itchy). Ear infections often smell fishy or yeasty too. Dogs with floppy ears, allergies, or frequent swimming are at higher risk. Head shaking and scratching at the ears are common clues. ### Why Does My Puppy Smell Like Fish? Puppies can smell fishy for all the same reasons adult dogs do. Their anal glands may not empty well yet, they may have soft stools, or they may have a skin infection. Puppies also get into things. Stool or urine stuck in the coat, especially around the rear end or in long fur, can create a fishy smell. Puppies with urinary tract infections may have accidents in the house, which owners sometimes mistake for normal puppy behavior. If your puppy has a fishy smell that does not go away after a bath, or if they are peeing more often than usual, call your vet. You can also read our guide on [why is my dog peeing so much](/knowledge/veterinary-medicine/symptom-guides/why-is-my-dog-peeing-so-much) for more on what frequent urination can mean. ### Diet and Grooming Sometimes the smell is simple. Some foods, especially fish-based diets, can change your dog's odor. If your dog swims in a lake or pond, the water and algae can leave a fishy smell on the coat. A bath with a dog-safe shampoo often fixes these cases. If the smell returns within a day or two, the cause is probably not grooming. ## Red Flags That Make It an Emergency Some signs mean you should not wait. Call your vet or an emergency clinic right away if you see any of these. - Your dog cannot pee at all, or is straining with nothing coming out. This can be a blockage and is life-threatening. - There is blood in the urine, or the urine is dark or cloudy. - Your dog is vomiting, lethargic, or refusing to eat along with the fishy smell. - Your dog has a swollen, red, or painful area near the anus. - Your dog is crying or showing pain when they pee or poop. - Your dog has a fever or is shaking. If you are not sure whether it is an emergency, call your vet. It is always better to ask. ## Safe Things You Can Do at Home While Waiting You cannot treat an infection at home, but you can keep your dog comfortable and avoid making things worse. - Give a bath with a gentle dog shampoo if the smell is on the coat. Do not use human shampoo, which can dry out your dog's skin. - Check the rear end gently. Look for swelling, redness, or a bad smell right at the anal area. Do not squeeze the anal glands yourself. You can cause injury or infection. - Wipe the urine area with a pet-safe wipe after your dog pees. This helps you track the smell and keeps the coat clean. - Encourage water intake. Fresh water helps dilute urine and supports bladder health. - Do not give human antibiotics, pain relievers, or leftover pet medicine. Some human drugs are toxic to dogs. - Keep a simple log. Note when the smell happens, how strong it is, and any other signs like peeing more or licking. This helps your vet. If your dog is licking their rear end constantly or seems uncomfortable, a vet visit is the right next step. Do not wait for it to get worse. ## What Your Veterinarian Will Check and Test Your vet will start with a full physical exam. They will check your dog's rear end, feel the anal glands, look at the skin and ears, and check for pain. For a fishy urine smell, the vet will collect a urine sample. They will run a urinalysis to look for bacteria, blood, and crystals. They may also send the urine for a culture to identify the exact bacteria and which antibiotics will work [1]. This step matters because different bacteria need different treatments. If your vet suspects a kidney infection, they may run blood work, including a C-reactive protein level [3]. Higher levels can help tell a kidney infection apart from a simple bladder infection. For skin and ear problems, your vet may take a sample of the skin or ear discharge and look at it under a microscope. This shows whether yeast, bacteria, or both are involved. For anal gland problems, your vet will check whether the glands are full, infected, or impacted. They may express the glands, prescribe medication, or recommend a diet change. If your dog has repeated urinary infections, your vet may look for underlying causes like stones, anatomical problems, or a weakened immune system. Some bacteria carry resistance genes that make treatment harder, which is another reason cultures matter [4]. ## Prevention and Monitoring You cannot prevent every fishy smell, but you can lower the odds. - Keep your dog at a healthy weight. Extra weight can make it harder for anal glands to empty. - Feed a balanced diet with enough fiber. Fiber helps firm up stool, which helps anal glands empty naturally. - Keep up with grooming. Regular baths and coat checks help you spot skin problems early. - Dry your dog's ears after swimming. Moisture in the ear canal encourages yeast and bacteria. - Watch for changes in pee habits. Peeing more often, straining, or accidents in a house-trained dog are early clues. Our guide on [how do I know if my dog has a UTI](/knowledge/veterinary-medicine/clinical-methods/how-do-i-know-if-my-dog-has-a-uti) walks through the signs. - Schedule routine vet visits. Your vet can check the anal glands, skin, and urine at regular exams. - If your dog has allergies, keep them managed. Well-controlled allergies mean fewer skin and ear infections. If your dog has bad breath along with other odors, that can be a separate issue. Our article on [why does my dog's breath smell like metal](/knowledge/veterinary-medicine/dental-care/why-does-my-dog-breath-smell-like-metal) covers that topic. ## Limitations and When to Contact a Veterinarian This article gives you general information, not a diagnosis. Every dog is different, and only your veterinarian can examine your dog and run the right tests. Call your vet the same day if your dog has fishy urine, is peeing more often, is straining to pee, or has a fishy smell that keeps coming back after a bath. Go to an emergency clinic right away if your dog cannot pee, is vomiting and lethargic, has blood in the urine, or has a swollen and painful area near the anus. Schedule a routine visit if the smell is mild, comes from the coat or ears, and your dog is otherwise acting normal. Your vet can check the anal glands, skin, and ears and decide whether treatment is needed. ## Frequently Asked Questions ### Why does my dog's urine smell like fish? Fishy urine is often a sign of a urinary tract infection. Bacteria in the bladder can change the smell of urine. Your vet will need a urine sample to confirm the cause and choose the right treatment. ### Is a fishy smell from anal glands normal? A small amount of fishy fluid is normal when anal glands empty. A strong or repeated fishy smell is not normal. It usually means the glands are not emptying well and may need a vet check. ### Can I treat a fishy smell at home? You can bathe your dog and keep the coat clean, but you cannot treat an infection at home. Do not use human medicine or leftover antibiotics. If the smell is in the urine or keeps coming back, see your vet. ### Why does my puppy smell like fish? Puppies can have the same anal gland, urine, or skin issues as adult dogs. They may also get stool or urine in their coat. If the smell lasts after a bath, or your puppy is peeing more often, call your vet. ### Does a fishy smell mean my dog is seriously ill? Not always. Anal gland fluid and grooming issues are common and not dangerous. But fishy urine, pain, vomiting, or a dog that cannot pee can be serious. When in doubt, call your vet. ## Related Articles - [Why Does My Dog's Breath Smell Like Metal? 5 Causes, Kidney Risks & Vet Guide](/knowledge/veterinary-medicine/dental-care/why-does-my-dog-breath-smell-like-metal) - [Why Is My Dog So Itchy?](/knowledge/veterinary-medicine/parasitic-diseases/why-is-my-dog-so-itchy) - [Why Does My Dog's Breath Smell Like Metal? Causes & Veterinary Solutions](/knowledge/veterinary-medicine/dental-care/why-does-my-dog-s-breath-smell-like-metal) - [Why Is My Dog Peeing So Much?](/knowledge/veterinary-medicine/symptom-guides/why-is-my-dog-peeing-so-much) - [How Do I Know If My Dog Has A Uti](/knowledge/veterinary-medicine/clinical-methods/how-do-i-know-if-my-dog-has-a-uti) - [Why Does My Dog Lick My Feet and Legs? Common Reasons](/knowledge/veterinary-medicine/clinical-methods/dog-keeps-licking-my-feet-and-legs) - [Why Does My Dog's Urine Smell So Bad? Causes and Fixes](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-urine-smell-strong) - [What Causes Dog Odor? Body, Breath, and House Smells](/knowledge/veterinary-medicine/skin-allergy-and-ear-care/dog-odor-causes) - [What Causes Bladder and Kidney Stones in Dogs?](/knowledge/veterinary-medicine/digestive-and-urinary-care/dog-bladder-kidney-stones-causes) ## References 1. [Prevalence and antimicrobial susceptibility profile of uropathogens in dogs and cats with signs of urinary tract infection](https://pubmed.ncbi.nlm.nih.gov/39537563/). The Journal of small animal practice, 2025. 2. [Genome-confirmed Pluralibacter gergoviae urinary tract infection in a companion animal in Peru](https://pubmed.ncbi.nlm.nih.gov/42385980/). Journal of global antimicrobial resistance, 2026. 3. [Retrospective evaluation of C-reactive protein for discriminating between lower urinary tract infections and acute pyelonephritis in dogs](https://pubmed.ncbi.nlm.nih.gov/42544488/). Journal of veterinary internal medicine, 2026. 4. [Silent carriage of mcr-9 on IncHI2 plasmid in an Enterobacter hormaechei strain causing a urinary tract infection in a dog from Portugal](https://pubmed.ncbi.nlm.nih.gov/42224776/). Veterinary microbiology, 2026. ## Further Reading - [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) - [American Veterinary Medical Association: Pet Care](https://www.avma.org/resources-tools/pet-owners/petcare)