What Are Yeast Infections in Dogs?
Does your dog frantically itch their skin? Have you noticed a bad smell or greasy fur when you pet them?
If so, they may have a yeast infection.
Yeast are fungal organisms that normally live on a dog’s skin without causing problems. However, when a dog’s immune system weakens or an underlying health condition, such as hypothyroidism, is present, yeast can overgrow and cause an infection.
The yeast that commonly causes skin infections in dogs is Malassezia, which grows on warm, moist areas of the skin. Yeast infections cause extreme itchiness and changes to the skin, such as thickening and discoloration over time.
Yeast infections are common among dogs of all ages.
While yeast infections in dogs are not considered medical emergencies, they should be treated by a veterinarian immediately to prevent symptoms from worsening. If left untreated, yeast infections can cause extreme discomfort, which can lead to a decreased appetite and lethargy, necessitating prompt veterinary care.
Because yeast infections typically develop secondary to an underlying illness or suppressed immune system, they are not contagious among dogs or to pet parents.
Types of Yeast Infections in Dogs
Yeast infections can affect various areas of the skin, including the ears, skin folds, paws, armpits, vulva, and groin.
Ears—Yeast infections of the ear—also referred to as yeast otitis—cause a thick, brown discharge and strong odor in the ear canal. Affected dogs repeatedly scratch their ears to try to relieve the discomfort. They may also shake their heads and develop a head tilt. Ear infections are commonly related to food allergies.
Skin—Yeast dermatitis refers to a yeast infection anywhere on the skin. Affected dogs have a musty odor, greasy coat, flaky or thickened skin, and hair loss. They tend to lick the affected areas of the body, which leads to brown discoloration of the skin over time.
Dermatitis, which is often due to allergies or a suppressed immune system, can affect a dog’s skin folds, armpits, vulva, and groin.
Paws—Yeast infections that affect the paws are generally related to environmental allergies, such as allergies to grass or pollen. Dogs constantly chew or lick their itchy paws, which leads to brown discoloration between the paw pads. Over time, open sores can develop on the paws.
Symptoms of Yeast Infections in Dogs
Signs vary depending on what area of the body is affected by the yeast infection.
Symptoms of yeast otitis may include:
Scratching of the ears
Thick, brown ear discharge
Red, inflamed ear canals
Symptoms of yeast dermatitis may include:
Brown discoloration of the skin
Frequent licking or chewing of the affected area
Greasy hair coat
Symptoms of a yeast infection affecting the paws may include:
Licking and chewing the paws
Brown discoloration of the skin and fur
Red, moist areas between the paw pads
Causes of Yeast Infections in Dogs
Yeast is opportunistic, which means that although it is naturally present on the skin, it can cause an infection when conditions are favorable.
A yeast infection can develop if a dog has a weak immune system or an underlying health condition. Underlying environmental or food allergies can predispose dogs to developing yeast infections.
How Veterinarians Diagnose Yeast Infections in Dogs
Your vet may use several tests to diagnose a yeast infection in your dog.
First, they will gather a through medical history, including when the symptoms started, if your pet is taking any medications, and if they have previously been diagnosed with any health conditions.
Next, your veterinarian will perform a full physical exam to check your dog’s overall health. They may also perform blood work to check for any abnormalities.
Additional tests will depend on what your veterinarian finds during the initial exam, but may include the following:
Tape impression—During this test, your vet presses a piece of clear tape to the affected area of skin to collect a sample. It’s then stained and examined under a microscope to identify yeast.
Cytology—A cotton swab is used to collect a sample from the affected area, and it is then rubbed gently onto a microscope slide. The sample is then stained and examined under a microscope to look for yeast.
Culture—A sterile cotton swab is used to collect a sample from the affected area. It is then sent to a lab to identify the type of organism present.
Skin biopsy—For chronic infections or those that are unresponsive to treatment, a small sample of skin can be taken and sent to a lab for a more accurate diagnosis.
Treatment of Yeast Infections in Dogs
If the infection affects only one area, a topical medication may be all that is needed. For more widespread infections, oral medications and frequent bathing can help resolve the issue.
Yeast otitis is typically treated with topical antifungal medications and steroids to reduce inflammation. Your veterinarian may recommend that you use a medicated ear wash prior to instilling ear medications.
Recovery and Management of Yeast Infections in Dogs
Because yeast infections often develop secondary to another health condition, they will not resolve without veterinary treatment.
Determining the underlying cause of the yeast infection and treating it accordingly improves treatment success. For example, if your dog has an underlying food allergy, an accurate diagnosis and treatment can help their skin improve.
It can take a few weeks to a few months for a yeast infection to fully resolve, depending on the severity. Most dogs start to feel relief from their symptoms in a week or two, but it can take several additional weeks for a pet parent to notice significant improvement to their skin and coat.
Prevention of Yeast Infections in Dogs
Additionally, health conditions that can lead to yeast infections can be caught and managed early during routine wellness visits.
Yeast Infections in Dogs FAQs
What food causes yeast infections in dogs?
Most of the food ingredients that cause allergies in dogs are proteins. Chicken is the most common food allergen related to yeast infections.
What happens if dog yeast infections go untreated?
If a dog’s yeast infection is left untreated, it will progressively worsen and lead to extreme discomfort. Over time, the discomfort can cause the dog to become very sick.
What should I feed my dog when they have a yeast infection?
Unless the yeast infection is due to an underlying food allergy, it’s generally fine to continue your dog’s usual diet. However, it is best to follow your veterinarian’s recommendations when deciding what to feed your dog.
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