Introduction
Yeast infections in dogs, also known as yeast dermatitis or Malassezia dermatitis, are fairly common skin conditions caused by an overgrowth of yeast on a dog’s skin. The yeast, Malassezia pachydermatis, is normally present on dogs’ skin in small amounts. However, an overgrowth can occur due to various factors like allergies, hormonal imbalances, and skin folds, leading to infection and inflammation.
Some owners report that their dog’s yeast infection symptoms seem to initially worsen when they begin treatment. This apparent worsening is thought to occur as the dog’s immune system reacts to the dying yeast organisms from the medication. While the infection itself has not gotten worse, the immune response can briefly cause more redness, itching, and irritation. However, with continued treatment, the symptoms should start improving within a few days or weeks as the infection clears up.
What Causes Yeast Infections in Dogs
Yeast infections in dogs are typically caused by an overgrowth of yeast that is naturally present on the skin and ears. The most common yeast found on dog’s skin is Malassezia pachydermatis. When the population of this yeast grows out of control, usually due to some trigger, it can lead to infection and inflammation [1].
There are several factors that can trigger an overgrowth of yeast:
- Moisture – Yeast thrives in warm, moist environments like folds of skin and ears.
- Allergies – Dogs with allergies and skin irritation can be more prone to yeast overgrowth.
- Antibiotics – Antibiotics kill off beneficial bacteria that keep yeast in check, allowing yeast to overpopulate.
- Diet – Food sensitivities and high sugar diets may contribute.
- Weakened immune system – Conditions that suppress the immune system can increase susceptibility.
Keeping dog’s skin dry and avoiding triggers like frequent antibiotic use can help prevent problematic overgrowth of yeast [2].
Common Symptoms
There are some key symptoms to look out for if you suspect your dog may have a yeast infection on their skin. Some of the most common symptoms include:
Red, greasy skin – Areas of infection often appear red, inflamed, and greasy. This is due to the overgrowth of yeast disrupting the normal skin environment. Patches of smelly, greasy skin are a hallmark of yeast dermatitis in dogs [1].
Odor – The moist, yeasty environment leads to a characteristic yeasty or musty odor coming from the skin. This smell can be quite pungent and apparent even from a distance.
Itching – Dogs will excessively lick, bite and scratch at infected areas due to the intense itchiness caused by the yeast infection. This can lead to further irritation, redness, hair loss and open wounds.
Hair loss – The areas of infection often exhibit patchy hair loss as dogs scratch, lick and bite at their skin. The infection itself can also damage hair follicles.
Do Symptoms Initially Worsen?
Many dog owners report that their pet’s yeast infection symptoms seem to get worse before improving. This temporary worsening of symptoms can be distressing but is often a normal part of the healing process.
There are a few possible reasons why yeast infection symptoms may appear to worsen at first:
- The antifungal medication can irritate the skin and cause redness, itching, and inflammation. This irritation is usually temporary as the infection starts to clear up.
- As the yeast dies off, the dog’s immune system reacts to the dead yeast cells, releasing histamines that cause itching and discomfort. This is essentially an inflammatory reaction as the body fights the infection.
- There may be a die-off effect where symptoms flare up as large numbers of yeast are killed by the antifungal medication.
According to veterinarians, owners often mistake this initial worsening of symptoms as a sign that the antifungal treatment is not working. However, worsening discomfort, redness, and itching in the first few days of treatment is commonly reported and does not mean the medication is ineffective. Symptoms should start improving within a week as the medication has time to clear the infection.
It’s important not to stop the antifungal medication too soon. Follow directions closely and allow several days for the treatment to work before expecting the yeast infection symptoms to subside. Contact your vet if symptoms worsen or persist beyond one week of starting treatment.
Diagnosis
A veterinarian will typically diagnose a yeast infection in dogs through a physical examination and diagnostic tests. The most common diagnostic methods include:
Veterinary Exam – The vet will look for clinical signs of a yeast infection such as redness, irritation, odor and discharge. They may take samples by lightly scraping the skin to check for yeast under the microscope.
Skin Scrapings/Cytology – Skin scrapings or tape strips allow examination of yeast and bacteria on the skin under the microscope. This is called cytology. Finding an increased number of yeast confirms the diagnosis.
Fungal Culture – A culture can be taken by swabbing the infected area. The sample is incubated to allow any fungal organisms like yeast to grow. A culture provides a definitive diagnosis by identifying the specific type of yeast.
Vets may also recommend blood work or other tests to check for underlying causes like allergies or endocrine disorders. Diagnostic testing is important to ensure proper treatment.
Sources:
https://www.smalldoorvet.com/learning-center/medical/yeast-infections-in-dogs/
Treatment
Treatment for yeast infections in dogs typically involves a combination of topical and oral antifungal medications prescribed by a veterinarian. Common prescription antifungals include ketoconazole, fluconazole, itraconazole, and miconazole.
Medicated antifungal shampoos can help treat infections on the skin and coat. These shampoos often contain chlorhexidine, miconazole, or ketoconazole. Bathing with a medicated shampoo helps kill yeast on the skin and reduce greasiness and scaling. Shampoo therapy may need to be continued regularly as part of maintenance treatment.
Dietary changes may be recommended, as yeast overgrowth can be triggered by food allergies. Dogs with yeast infections may be transitioned to a hydrolyzed protein or novel protein diet trial to identify and eliminate problem ingredients. Probiotics can also help rebalance gut bacteria.
For recurring infections, vets will aim to identify and address any underlying causes or risk factors like allergies, endocrine disorders, or skin folds. This may involve allergy testing, hormone panels, or surgery to correct anatomical defects contributing to infection.
Improving Symptoms
Although yeast infections in dogs can be irritating and uncomfortable, it’s important to understand that the medications prescribed take some time to work fully. As the VCA explains, while most cases will show some improvement within a week, completing the full course of treatment is essential for clearing the infection entirely. This usually takes a minimum of a few weeks.
Owners should be prepared that symptoms may seem to briefly worsen when starting treatment, before improving. As Vets4Pets notes, anti-fungal medications often stimulate the yeast to grow rapidly at first, which is part of the treatment process. Sticking with the medication and managing expectations around the timeline are important.
With appropriate treatment and owner diligence, most yeast infections in dogs can be controlled and resolved over time. But stopping treatment early risks a recurrence. Completing the full course as prescribed by your vet is key to successfully improving symptoms long-term.
Prevention
There are several ways to help prevent yeast infections in dogs:
Keep Areas Dry: It’s important to keep the folds, ears, and paws dry. Gently pat dry these areas after baths or swimming. Trim hair around folds to allow better airflow.
Avoid Excessive Antibiotics: Antibiotics kill both good and bad bacteria, which can allow yeast to overgrow. Only use antibiotics when truly necessary and under veterinary guidance. Consider probiotic supplements during and after antibiotic treatment.
Diet: Some studies show that carbohydrate-rich diets may promote yeast growth. Consider a low-carb or ketogenic diet under veterinary supervision.
Probiotics: Probiotic supplements support healthy populations of bacteria to keep yeast in check. Examples include Fortiflora, Proviable, and Purina Veterinary Diets Pro Plan FortiFlora.
When to See the Vet
If your dog’s yeast infection symptoms persist or seem to worsen despite home treatment, it’s important to make an appointment with your veterinarian. Signs that the infection is not improving or getting worse can include increased itching, redness, swelling, odor, or discharge. You should also watch for signs of secondary skin infection, like pustules, crusting, or hair loss, which indicate bacterial infection may have set in.
According to PetMD, you should contact your vet promptly if your dog exhibits lethargy, loss of appetite, vomiting, or other signs of systemic illness that could be related to the yeast infection [1]. These types of symptoms may point to the infection spreading internally beyond just a localized skin or ear issue.
Your vet can prescribe antifungal medication, medicated shampoos, or other treatments to clear up the infection if over-the-counter options aren’t working. They can also rule out other potential causes for your dog’s symptoms. Don’t try to treat a severe, widespread, or worsening yeast infection at home without contacting your veterinarian first.
Conclusion
To recap, while yeast infections in dogs may cause symptoms to initially worsen as the infection proliferates, diligent treatment and patience are key. Working closely with your veterinarian, following their prescribed treatment plan, and allowing time for the medications to work will help get your dog’s infection under control. Though it may seem like things are getting worse at first, stick with the treatment protocol. With your dog’s immune system fighting back and the antifungal medications attacking the infection, you should start seeing real improvement within a few weeks. Don’t lose hope – yeast infections in dogs can get better with proper veterinary care and attention.