Fluconazole for Dogs

PetMD’s medications content was written and reviewed by veterinary professionals to answer your most common questions about how medications function, their side effects, and what species they are prescribed for. This content shouldn’t take the place of advice by your vet.

What Is Fluconazole Used for in Dogs?

Fluconazole is a prescription antifungal medication used to treat systemic (widespread internal) fungal and yeast infections.

Fluconazole is often prescribed to dogs to treat fungal infections such as:

• Cryptococcosis

• Valley Fever (coccidioidomycosis)

• Aspergillosis

• Candidiasis

• Dermatophytosis (ringworm)

• Histoplasmosis

• Blastomycosis

Fluconazole may also be used for the treatment of yeast and ringworm infections of the skin, ears, and nails.

Fluconazole is also prescribed for the treatment of susceptible fungal infections in other species including cats, horses, birds, and rabbits.

Depending on the pet being treated and the type of infection, certain antifungals may work better than others, such as itraconazole, ketoconazole, or topical preparations.

Your veterinarian will determine the best medication based on your pet’s needs and symptoms.

While fluconazole is FDA-approved for human use in oral tablet and liquid suspension formulations under the brand name Diflucan® and the generic fluconazole, fluconazole is not currently FDA-approved as a veterinary medication.

It is, however, readily utilized in the veterinary field, and veterinarians can legally prescribe certain human drugs in animals in certain circumstances. This is called extra-label or off-label use because this use isn’t described on the drug label.

In certain circumstances, your veterinarian may recommend a compounded formulation of fluconazole.

Compounded medications are prescribed if there’s a specific reason your pet’s health can’t be managed by an FDA-approved drug, such as if your pet has trouble taking pills in capsule form, the dosage strength is not commercially available, or the pet is allergic to an ingredient in the FDA-approved medication.

Compounded medications are not FDA-approved. They are created by either a veterinarian or a licensed pharmacist on an individual basis to best suit a patient’s particular needs.

Fluconazole Considerations in Dogs

Fluconazole should be used with caution in pets with liver disease, and in pets that are pregnant or nursing.

Fluconazole can have significant interactions with other medications. It’s important to discuss your pet’s medications, including vitamins and supplements, and medical conditions with your veterinarian.

If your pet has kidney disease, your vet may recommend a lower or reduced dose.

Speak with your veterinarian about your pet’s condition and whether this medication is right for them.

How Fluconazole Works in Dogs

Fluconazole works as an antifungal medication by blocking the fungi’s ability to create an enzyme needed to produce their cell membranes. This stops the metabolism and growth of a given fungus.

Fluconazole is often used when fungal infections occur in the nervous system or urinary tract, due to its ability to penetrate those spaces.

Directions for Fluconazole for Dogs

Follow the directions on the drug label or as provided by your veterinarian.

Generally, fluconazole may be given with or without food. If your pet is experiencing digestive upset after being given this medication on an empty stomach, try giving it with a small meal.

Missed a Dose?

Speak with your veterinarian about what to do if you forget to give a dose of fluconazole.

Generally, your vet may instruct you to give it when you remember or, if it is almost time for your pet’s next dose, to skip the missed dose and resume your normal dosing schedule. Do not give extra or double doses.

Possible Side Effects of Fluconazole in Dogs

Fluconazole is generally well tolerated in dogs, but the following side effects may occur:

• Loss of appetite

• Vomiting

• Diarrhea

• Hair loss

• Eye discharge

• Dry skin

• Lethargy

• Liver irritation

Symptoms of liver irritation may include:

• Vomiting

• Loss of interest in food

• Yellow gums, skin or whites of the eyes

Human Side Effects

Fluconazole is also a prescription medication for humans, frequently with dosages different from those prescribed for your pet by a veterinarian.

Due to possible side effects, humans should never use medicine dispensed for their pets, and pets should not be given any medicine dispensed for a human’s use.

If you accidentally ingest a medication prescribed for your pet, call your physician or the national Poison Control Center hotline at 1-800-222-1222.

Monitoring Your Pet

Specific monitoring or routine testing while your pet is on this medication may be recommended by your veterinarian depending on your pet’s individual needs, other medications they may be on, and/or the issue that initially caused your pet to be placed on this medication.

If your pet is on fluconazole long-term, your veterinarian may monitor your pet for changes in liver function.

When To Call Your Vet

Call your veterinarian if any of the following apply:

• Severe side effects are seen (see above)

• Your pet’s condition worsens or does not improve with treatment

• You see or suspect an overdose

• You have additional questions or concerns about the use of fluconazole

Fluconazole Overdose in Dogs Information

There is limited information on overdoses of fluconazole. Only large overdoses are likely to cause a toxic overdose.

Signs of a fluconazole overdose in dogs may include:

• Shallow breathing

• Drooling

• Urinary incontinence

• Blue gum color

• Vomiting

• Diarrhea

If you suspect an overdose, immediately contact your veterinarian, seek emergency veterinary care, or contact an animal poison control center. Consultation fees often apply.

• Pet Poison Helpline® 855-764-7661

• ASPCA® Animal Poison Control 888-426-4435

How To Store Fluconazole for Dogs

Follow these tips when storing your pet’s fluconazole:

• Fluconazole should be stored at controlled room temperatures below 86 degrees F (30 degrees C).

• Liquid fluconazole should be stored at room temperatures between 41–86 degrees F (5–30 degrees C); avoid freezing.

• Keep the container tightly closed to protect it from moisture and light.

• Compounded medications should be stored according to the compounding pharmacy’s label.

• Keep out of reach of children and pets.

• Always confirm storage requirements by reading the label.