Review of the Antifungal Itraconazole Use in Pets

Fungal Infections and the use of Itraconazole in Pets

Any mammal can contract fungi through the air, soil, or contaminated food at any time. Fungal parasites are single-celled organisms ingested either orally or inhaled. Certain fungi are directly responsible for certain systemic diseases.


Itraconazole Antifungal Capsules for Pets

Itraconazole Antifungal Capsules Available at VetRxDirect

Itraconazole is a prescription antifungal drug used to fight systemic fungal infections in cats and dogs. How common are they?  Because these organisms grow slowly and are difficult to control, the drugs must be administered for a protracted period of time. Unlike antibiotics, medications which kill yeast and fungi are often prescribed for several weeks, even months.

When an infection has been confirmed, veterinarians often prescribe Itraconazole for serious illnesses demanding long-term treatment.  You dog’s veterinarian will most likely recommend a powerful antifungal to be taken on a regular basis for at least two months. Only after all symptoms have subsided can the treatment be safely discontinued.

How to Administer Itraconazole Medication to Pets

Just as with people, drug schedules and dosages must be adjusted based on age, weight, and the severity of the condition or disease. It is the job of your veterinarian to determine exactly how much and how often your dog or cat should take this medicine. For most pets, the easiest and most effective way to give Itraconazole is to put it in food. But if you happen to miss giving a dose, do not double it to catch up, since the medication is quite potent.

In order to improve absorption, it is often a good idea to pair Itraconazole with a high-fat food, such as cheese, butter, or fatty meats.  The medication should be administered until otherwise advised by your veterinarian. Failing to complete the full treatment will greatly increase the risk of recrudescence, i.e., the disease may come back!

Side effects of Itraconazole in Pets

Almost all drugs have the potential of side effects. Fortunately, Itraconazole has fewer than most. The most common side effects are loss of appetite and liver toxicity, both of which are quite rare. That said, these side effects should always be reported to your veterinarian as soon as possible. Failure to do so could result in more serious health problems over the course of the treatment.

Precautions of Itraconazole Use in Pets

Like all prescription drugs, Itraconazole should be kept out of the reach of children. It should only ever be administered according to your veterinarian’s express directions.  The medication should only be given to the animal for which it was prescribed and never to another pet or person. Because it is passed through the milk, Itraconazole is generally not prescribed to pregnant pets.

Interactions of Itraconazole with Other Medications in Pets

Generally safe to take with other medications, the effectiveness of Itraconazole may be greatly reduced if the patient is taking antacids or drugs used to decrease stomach acid, since it will limit the amount of Itraconazole absorbed. Pet owners should consult their vets before they administer Itraconazole in conjunction with another prescription drug or even a supplement.

Overdose Warnings of Itraconazole in Pets

As class of drugs, antifungals are quite powerful. If an animal accidentally ingests more than prescribed  it is imperative to contact your local Animal Poison Control Center immediately. Make sure you bring the prescription container with you when your pet is taken in for emergency treatment.


Whenever there is any sign of a serious systemic fungal infection, Itraconazole is the most commonly prescribed drug at the outset. Because it can be used to combat a whole host of infections, including blastomycosis, aspergillosis, cryptoccocosis, and more, the drug is considered a sort of panaceas where fungal infections are concerned. Of course, once the doctors complete additional tests and they are able to identify the infection, they my combine Itraconazole with an injectable antibiotic for up to one month.

Which Pets are at Risk of Contracting a Fungal Infection?

Aspergillosis is the most common type of fungal infection and is found in grass clippings, hay, straw, and dust. It is considered an opportunistic disease because it targets both cats and dogs and is nearly ubiquitous in some environments. As a general rule, it is much more common in younger pets, since they have immature immune systems to fight off the invading infection.  Because they have longer heads and noses and more sensitive nasal cavities, dogs are more likely to suffer from these infections than cats.

Has your pet suffered from a fungal infection where Itraconazole was used? Are there any lessons from the experience you would like to share with us? Please leave any comments you have below.

Thank you,



11 thoughts on “Review of the Antifungal Itraconazole Use in Pets

  1. After first two days of treatment there was a five day gap. Dog began vomiting on day 2 of 5 day gap and vomits at night and during the day since.its now day 4 of first 5 day gap- and I’m still waiting for feedback from my vet.
    Dog is large female basset- 8 years old- disease was 2 Sporanox caps with meal each day for two days.

  2. Our 9 month old chocolate lab was diagnosed with blastomycosis about a week ago and is now taking this medicine. She is still lethargic and has had a couple of ulcers that appeared then drained in their own. Her appetite is not good. Eating little bits by hand but she is drinking. How long before we start to see some improvement in her? Thanks

    • Hello, I am from India. I have seen improvement after 4-6 weeks of application for all street dogs who has administered this one.

    • Our Standard Poodle had 4 1/2 month of treatment and two follow up blood test to make sure the infection was gone. He was 95 bs. Before treatment and lost 20 lbs. I was just there with him and at times hand fed him or got creative with the dog food. He drank alot of water. But most of the time he was very lethargic. I just kept him company and watch over him. We had to wait 6 mos. after recovery to have ACL. Surgery. He is now bouncing around. If you are a person of faith this is a time of spiritual need for both you and your dog.

  3. Our 5 year old male Standard Poodle had Blastomycosis in the Fall of 2017. It was not diagnosed til Jan. In which I kept taking him back the vet because a snorting sound no other noticable symtoms. Sent to a Specialty vet who did a nasal samples misdiagnosed as cancer until it was relooked at as Blastomycosis. We put our dog on Sporomax bought through pharm. in Canada due to the fluctuations in pricing in US. Max had high liver enzyme levels while on the med. developed lesions on torso and tail and was treat for that with shampoos and antifungal spray. Towards the end of treatment had severe ear infection and had meningitis. He is alive and well after 1 1/2 years. Has anyone had any side effects in their dogs after treatment and recovery.

  4. My 3 year old GSD has been diagnosed with Disseminated Aspergillosis and he has been on Itraconazole for 22 days. He has not been eating very well. Being hand fed his dry food everyday as a bit of a play. I have been also giving him cooked beef and veggies, egg and cheese before his tablets. He seems alright so far, although the vet did not give us much hope….so fingers crossed he is good so far…Would like to know of other pet owners who have managed Aspergillosis on this medication and if they got good results or not.

    • I have a Shih Tzu that had this terrible stuff. He was on medicine for 6 months and got a negative text almost three months ago. I am so worried about relapse. But for now… he is great. Good luck to you and your pup.

    • Good Day
      Our 8 yo Doodle just got diagnosed with the same illness. Just started to give him Itraconazole 100mg twice a day

      I know you published on 9/10/10,, any updates?


    • What has been your outcome to date? My Australian shepherd/cattle dog was diagnosed with aspergillosis and has been on Itraconazole for several weeks. He has good appetite and wants to play again, but he seems to be losing muscle and hair shedding is really bad when brushing him.

  5. My beagle got this crap in August 2019.Coughing and high fever.He started this medicine..Itraconazole once his test results came back which took a few weeks!! So Sept.2019 he started the meds.My only advice is to try to keep the fever down.I did that with rimadyl ..only when I had too.His temp spiked one night to 105.7.I thought he was a goner! If you can’t take their temps..either learn how of just give rimadyl once a day.My other advice is don’t let them stop eating.I feed boiled hamburger with rice and boiled chicken with rice and also a good quality canned dog food I got from the vet.They just don’t want to eat when they are sick like this and they get SICK! The meds will upset their stomach and cause vomiting.Feed small amounts all day long.Nothing else helps with the cough so don’t waste your money on more meds.At least it didn’t help with my beagle.Just keep them comfy.He is still on the meds but so much better.He is running rabbits again.Eating his regular food.It took about 4 weeks to see an improvement with him.This is a nasty infection or disease..whatever you call it.Some dogs don’t make it.:(

  6. My 7 year old Ragdoll got a fungal infection in his nose and was treated with Itraconazole. After 6 weeks of not eating and force feeding, he got odema in his leg followed by a really bad dermatis with hair loss down one arm, under his arm, foot and chest and which I am still trying to clear up. The vet gave me burn cream for the dermatitis which has not helped. Vet wasn’t much help, just kept telling me he had lost a third of his body weight. I found out that Anorexia, Odema and dermatitis are all side affects of Itraconazole so I stopped the drug and the very next day he started to eat again. He is eating twice as much as before he got sick, the swelling in his legs has gone down and I am still trying to clear up the dermatitis. My 3 kilo baby was put on 50 mg a day of Itraconazole and I was not told to give it with food.

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