Itraconazole for Cockatiels: Uses, Dosing & Side Effects

This information is for educational purposes only. Never give your pet any medication without your veterinarian's guidance. Dosing, frequency, and safety depend on your pet's specific health profile.

Itraconazole is a prescription azole antifungal medication. It works by interfering with the fungal cell membrane, which helps slow or stop the growth of certain yeasts and molds. In birds, it is most often discussed for systemic fungal disease, especially respiratory fungal infections such as aspergillosis.

For cockatiels, itraconazole is usually used extra-label, meaning your vet prescribes it based on avian experience and published veterinary references rather than a cockatiel-specific FDA label. That is common in bird medicine. The exact formulation matters, because absorption can vary between capsules, oral solution, and compounded liquids.

This medication is not a home treatment. Cockatiels can become very sick from fungal disease, and they can also be sensitive to medication errors because of their small body size. Your vet may pair itraconazole with supportive care, changes to the environment, and follow-up testing to make sure treatment is helping and not causing harm.

In cockatiels, itraconazole is most commonly used when your vet is treating or strongly suspects a fungal infection. The best-known example is aspergillosis, a respiratory disease caused by Aspergillus species. Birds with aspergillosis may show voice changes, tail bobbing, open-mouth breathing, exercise intolerance, weight loss, or a long history of vague illness.

Itraconazole may also be considered for some other fungal infections when culture, imaging, cytology, or the bird's clinical picture supports that choice. In pet birds, fungal disease can affect the air sacs, lungs, sinuses, or digestive tract, and treatment often lasts weeks to months rather than a few days.

Because respiratory signs in cockatiels can also come from bacterial infection, chlamydiosis, air sac mites, heart disease, toxins, or egg-related problems, itraconazole should not be started based on symptoms alone. Your vet may recommend radiographs, bloodwork, endoscopy, or fungal testing before or during treatment.

Published avian references commonly list itraconazole at 5-10 mg/kg by mouth every 12-24 hours in birds, with Merck also noting 10 mg/kg by mouth every 24 hours in birds and pet-bird guidance describing 5-10 mg/kg once to twice daily for systemic infection. That said, a cockatiel's actual dose must be calculated by current body weight in grams, the exact formulation, the suspected fungus, and your vet's comfort with avian antifungal therapy.

In real practice, your vet may choose a lower end of the range to start, especially in a small bird, then adjust based on response and tolerance. Treatment is often prolonged. It is common for birds with aspergillosis to need several weeks to several months of medication, plus rechecks.

Give itraconazole exactly as labeled by your vet. Do not switch between a human capsule, a cat liquid, and a compounded suspension unless your vet tells you to, because the concentration and absorption may differ. If you miss a dose, contact your vet for instructions rather than doubling the next dose. If your cockatiel stops eating, seems weaker, or shows worsening breathing effort during treatment, see your vet promptly.

Itraconazole is often better tolerated than some older antifungals, but side effects still matter in cockatiels. The most important concerns are decreased appetite, vomiting or regurgitation, diarrhea or loose droppings, weight loss, lethargy, and liver irritation. In birds, even a short drop in food intake can become serious quickly.

Call your vet if your cockatiel becomes fluffed up, unusually sleepy, less vocal, reluctant to perch, or starts eating less. Those signs are not specific, but they can mean the bird is not tolerating the medication well or the underlying fungal disease is progressing.

More serious warning signs include yellow or green urates, persistent vomiting, marked weakness, severe diarrhea, abdominal discomfort, or worsening breathing effort. Your vet may recommend repeat weight checks and bloodwork, especially if treatment will continue for a long time or if your bird already has liver concerns.

One avian caution worth knowing: some parrot species, especially African grey parrots, have been reported to be more sensitive to itraconazole. Cockatiels are not the classic species flagged for that problem, but the warning is a reminder that birds can respond differently than dogs and cats, so close veterinary monitoring is important.

Itraconazole can interact with other medications because azole antifungals affect liver enzyme metabolism and can also compete at P-glycoprotein transport pathways. That means blood levels of some drugs may rise, and the risk of side effects can increase.

Important interaction categories include antacids and acid-reducing drugs, which can reduce absorption of itraconazole; benzodiazepines, calcium channel blockers, cisapride, corticosteroids, and other drugs that rely on liver metabolism. Merck also notes that azoles should be used very carefully with other potentially liver-toxic medications.

For cockatiels, the practical rule is straightforward: give your vet a full list of everything your bird receives, including compounded medications, supplements, probiotics, crop medications, nebulized drugs, and over-the-counter products. Do not assume a supplement is harmless. If your bird is on long-term therapy, your vet may adjust timing, choose a different antifungal, or monitor liver values more closely.