A fungal infection isn’t much fun for a dog. It can be itchy, uncomfortable, and downright inconvenient. It’s not much fun for dog owners either – after all, no one wants to see their pet in discomfort. What some people don’t always realize is that fungal infections aren’t just a surface complaint: certain infections can develop internally, and can often affect the brain or central nervous system. In these kinds of cases, slapping some cream on the affected area isn’t going to work. A drug that’s capable of crossing the blood-brain barrier, on the other hand, just might.
Fluconazole is just such a drug. Despite not being approved for animal use by the FDA, vets are permitted to legally prescribe it as an ‘off label’ or ‘extra-label’ drug. Although it’s vital to use it only as your vet prescribes, Fluconazole is considered a safe treatment for yeast fungal infections (especially those that have developed in the brain or spinal cord) in dogs. Typically, it will be prescribed under brand names like Diflucan or Trican. Here’s exactly what you need to know about Fluconazole, its uses, its dosage, and its possible side effects.
Fluconazole for Dogs
Fluconazole is typically prescribed to treat fungal skin infections in dogs. Thanks to its ability to cross the blood-brain barrier, it’s also used to treat more serious infections such as Blastomycosis and Histoplasmosis, as well as in situations where other anti-fungal medications have failed. As avriorx.com outlines, some of the conditions it’s most commonly used to treat include:
- Superficial candidiasis (ringworm)
- Cryptococcal meningitis
- Skin infections
- Urinary tract infections
- Central nervous system infections
- Brain and spinal cord infections
Dosage of Fluconazole for Dogs
Typically, dosage will be between 5.5 mg and 22 mg per pound of a dog’s weight, administered either once every 12 hours or once every 24 hours. However, as the recommended dosage depends on your dog’s general health, age, size, and the condition being treated, be sure to follow your vet’s advice to the letter. This applies as much to the length of treatment as to the dosage: while Fluconazole is absorbed quickly, the length of time before you notice an improvement will depend on the condition. Some infections will clear up within a few weeks; others may take several months to treat.
How is Fluconazole Administered?
Fluconazole is usually prescribed in the form of either a tablet or liquid medicine. Occasionally, it may be given by injection, in which case your veterinarian will administer it directly. In the case of both tablet and liquid forms of medication, the treatment can be taken on either an empty stomach or after food. Some dogs don’t tolerate any type of medicine without food: if your dog vomits after taking the medication, give it to them alongside a small meal or treat in the future.
What Should I Do if I Forget a Dose?
While the success of any medication depends on ensuring regular administration, accidents can and do happen. If you forget to give your dog their medication at the usual time, take the advice of vcahospitals.com and either give them the dose once you remember or, if it’s closer to the time for the next dose than it is the one you missed, skip the missed dose and carry on with your regular dosing schedule as normal. Don’t be tempted to double up on a dose or add extra doses: it won’t increase efficacy and may result in an overdose.
Are There Any Side Effects I Should Be Aware of?
Although Fluconazole is considered a safe drug, certain side effects have been observed. The side effects in dogs are similar to those in humans, namely:
- Dark urine
- Heart rhythm disturbances
- Decreased appetite
- Renal failure
While not specific to Fluconazole, all medications carry the risk of an allergic reaction. If your dog displays any symptoms of an allergic response (hives, swelling, breathing difficulties, or excessive itchiness), discontinue treatment and contact your vet immediately.
Is Fluconazole Suitable for all Dogs?
Fluconazole may be an effective treatment, but it’s not suitable for all dogs. If your pet has liver or kidney failure, proceed with caution and always make sure that your vet is aware of your pet’s medical history prior to prescribing the drug. The same advice applies to nursing or pregnant dogs. If your dog has ever experienced an allergic reaction to Fluconazole in the past, let your vet know so they can explore other treatment options.
Are There Any Drug Interactions I Should Be Aware Of?
As marvistavet.com notes, Fluconazole has been known to increase the efficacy of the following drugs, thus increasing the possibility of side effects:
- Amphotericin B
- Diuretics (thiazides)
- Macrolide antibiotics
- Non-steroidal Anti-inflammatories
- Vincristine/ vinblastine
- Sulfonylurea antidiabetic agents
If you give any form of herbal supplements, vitamins, or minerals to your dog, make sure you let your vet know prior to treatment. Avoid introducing any new supplements to their regime midway through treatment without first consulting your vet.
Will I Need to Visit the Vet During Treatment?
If Fluconazole is prescribed for a minor infection that is expected to clear up within a few days of the treatment plan commencing, it’s unlikely your vet will ask to see you while the treatment is ongoing. They may need to check your dog at the end of treatment to ensure all the symptoms have resolved, but other than that, you’ll probably only need to check in with them if you notice any adverse reactions to the medication. If, on the other hand, your vet has prescribed a long-term course of Fluconazole to treat an established or severe infection, they will need to monitor your pet throughout treatment for any signs of a change in liver function.
What Should I Do If I Suspect an Overdose?
Although Fluconazole is considered a safe drug for dogs, any possibility of overdose should be taken seriously. If you accidentally double-up on a dose or administer more than the prescribed amount, contact your vet as soon as possible. Likewise, notify them immediately if you notice any adverse reaction to a standard dose. If it’s outside the surgery’s standard opening hours, don’t wait for them to open the next day: contact an emergency facility and work according to their instructions.