Why Do My Dogs Smell Like Fish?

Dogs often have an odor to them, which can result from various factors, including rolling in dirt, or in more serious cases, an underlying medical condition.

Some dogs have a natural odor, while others may have an unusual or unnatural smell attributed to the food they eat, their overall health, or something they have been exposed to in the environment.

One common concern for dog parents is when their canine companion smells like fish. Often, this fishy smell is unnatural and can be a sign of an underlying health issue in your dog for which veterinary attention is needed.

Why Do Dogs Smell Like Fish?

One of the most common reasons your dog might smell like fish is due to anal gland secretions. Other potential causes include dental disease, urinary tract infections (UTIs), vaginal and other female-related infections, skin conditions such as yeast infections, or the type of food they eat.

When you notice this fishy smell coming from your dog, it’s a good idea to try to figure out where it is coming from, as this can help determine the underlying cause. Inspecting your dog from nose to tail can help pinpoint the source of the stink.

If your dog has fishy breath, it could be due to a dental infection or to their diet, such as fish-based food or treats or supplements like fish oils.

In female dogs, a fishy odor from their genital area may be caused by urinary tract infections, pyometra (uterine infection), or vaginitis (inflammation or infection of the vagina). Anal gland issues can also lead to a fishy odor from the dog’s rear end. In male dogs, a urinary tract infection can produce a fishy smell, depending on the underlying bacteria.

While not all causes of a dog smelling like fish are necessarily a medical concern, it’s always important to have the situation evaluated by your veterinarian to rule out something serious. For instance, pyometra in a female dog can be life-threatening if not treated right away.

Anal Glands and Sacs

Dogs have two small anal glands on either side of their rectal opening, typically secreting a foul-smelling fluid, often resembling a fishy odor. If your dog emits this fishy smell from their anal glands, it does not necessarily mean they are having a medical problem. Normally, these anal glands are expressed during a bowel movement.

You may not detect the scent if your dog’s stool is regular. However, when these glands become infected, impacted, or too full, you will smell the fishy secretions, indicating the need for medical intervention.

Signs of full anal glands include:

• Excessive scooting

• Licking

• Straining to defecate

• Not wanting to sit

• Redness/swelling of the anus

In some cases, dogs may release fishy-smelling anal gland secretions when they are startled or scared, which is considered normal and part of their fight-or-flight response.

This may be accompanied by shaking, panting, barking, whining, hiding, excessive licking, or other signs of stress or anxiety.

Urinary Issues

In dogs, urinary issues can cause a fishy smell to come from their genital area, a situation seen more frequently in females. UTIs may cause fishy-smelling urine due to an overgrowth of bacteria in the bladder or kidneys.

Other signs of UTIs include:

• Excessive water consumption
• Frequent urination
• Urinary accidents
• Straining to urinate with little to nothing coming out
• Changes in urine color

Severe kidney infections can result in lethargy, vomiting, decreased appetite, or fever.

Vaginitis can also produce a fishy smell in female dogs. It is commonly caused by bacteria or yeast from urine or the environment. Structural abnormalities such as a hooded vulva (common in English Bulldogs) or foreign material such as dust or dirt in the vagina can also cause vaginitis.

Vaginitis can occur in dogs of any age, including puppies, and can have symptoms very similar to pyometra in unspayed females.

Pyometra is a life-threatening infection of the uterus, which is related to hormonal changes in the female dog’s reproductive system. Both vaginitis and pyometra can have a fishy odor.

If your dog is showing any signs of a UTI, vaginitis, or pyometra, they should be seen by their vet or an emergency vet right away for diagnosis and treatment.

Dental Diseases

If you are noticing a fishy smell coming from your dog’s mouth, it may be due to bacterial overgrowth in the mouth caused by dental issues.

Tooth root infections, infected mouth wounds, and periodontal disease can lead to an overpopulation of normal mouth bacteria, resulting in an unpleasant fishy odor.

Other signs of dental disease in dogs include:

• Decreased appetite

• Tartar buildup on teeth

• Dropping food while eating

• Drooling

• Pawing/rubbing the face

• Swelling of the face or mouth

Certain dog breeds are more prone to dental issues due to genetics (such as the Yorkshire Terrier, Chihuahua, Dachshund, and Labrador Retriever), the shape of their head (such as brachycephalic dogs like the Pug, Boxer, and Shih Tzu), or other factors.

If you notice this odor and/or other signs of dental disease in your dog, they should have a checkup with their vet to evaluate the need for a professional dental cleaning.

After a dental procedure, the use of a special diet, dental chews, daily teeth brushing, or a special water additive can be helpful to prevent the odor or infection from returning.

Skin Infections

Yeast skin infections in dogs, commonly in areas like the paws, face, ears, genital region, and skin folds of the back legs, can have a fishy or corn chip–like odor. These infections often result from allergies or itching. Additional signs include excessive licking/itching, redness, scabs or sores, and hair loss.

Antifungal medications, including oral and topical preparations (shampoos or wipes), can be helpful, depending on the extent of the skin infection.

If you suspect your dog has allergies or they have an odor to or lesions on the skin, they should be seen by their vet for a checkup and skin diagnostics to determine the underlying cause, which may be yeast-related.

How To Get Rid of Your Dogs' Fishy Smell

To get rid of a dog’s fishy smell, start by identifying the source of the odor. If it’s coming from their mouth and they don't eat a fish-based diet or treats, this could be related to dental issues.

Begin by brushing their teeth and giving them a dental chew unless other symptoms warrant a vet visit.

For skin-related odors, consider using a medicated shampoo designed to address both bacteria and yeast overgrowth on the skin.

If there is inflammation or redness, particularly in cases like vaginitis, you can use medicated wipes on the affected areas.

However, if your dog has vaginal discharge with or without a fishy odor, you should have them seen by their vet as soon as possible without trying any home remedies first.

Dogs who scoot or have a fishy odor from the anal area should also be taken to their veterinarian to have the glands expressed and examined for more serious potential issues like abscesses or tumors.

Fiber supplements and probiotics can help with anal gland problems.

Medicated wipes can also address the fishy smell around the rectum from the anal glands.

These remedies are OK to try while waiting for an appointment with your vet, unless the symptoms suggest a more serious condition, such as a kidney infection or pyometra.