Is Apoquel (Oclacitinib) Toxic to Cats and Dogs?
Apoquel (oclacitinib) is an immunosuppressant for dog allergies — mildly toxic to dogs, moderately concerning for cats. Poison hotline reports of pet exposures are rising.
Can cause real harm — call a vet for guidance.
Usually minor, but watch for symptoms.
In an emergency, do not wait.
Medical disclaimer: This tool is for general information only and isnot a substitute for veterinary diagnosis or treatment. Toxicity depends on the amount, your pet’s size, and health history. If your pet may have ingested something harmful, contact your veterinarian or a poison control hotline ((888) 426-4435 / (855) 764-7661) immediately — do not wait for symptoms to appear.
What is Apoquel (Oclacitinib)?
Apoquel (oclacitinib) is an immunosuppressant for dog allergies — mildly toxic to dogs, moderately concerning for cats. Poison hotline reports of pet exposures are rising.
Also known as: oclacitinib, apoquel tablets, apoquel 16mg, apoquel 5.4mg, zenrelia, itch medicine for dogs, allergy pills for dogs.
Symptoms to Watch For
🐈 In Cats
- Vomiting and drooling within hours
- Lethargy and reduced appetite
- Wobbliness or unusual behavior
- Cats are not routinely dosed with oclacitinib, so an accidental dose warrants a vet call
🐕 In Dogs
- Vomiting, diarrhea, and soft stools after eating multiple tablets
- Lethargy and reduced appetite
- Large overdoses can suppress the immune system, raising infection risk
- Pre-existing skin or ear infections may worsen temporarily
What to Do If Ingested
- Remove the bottle and count how many tablets are missing.
- Note the tablet strength (5.4 mg, 16 mg) and your dog's weight.
- Offer water and watch for vomiting over 24 hours.
- Call a vet or poison hotline with the strength and count for dose guidance.
Steps apply to both cats and dogs. When in doubt, call a vet or poison hotline before acting. Have a cat? Run the Pet Poison Triage Wizard for cat-specific steps.
When to Call the Vet Immediately
Call your veterinarian or a poison control hotline right away if you notice any of these:
- Many tablets were eaten, especially by a small dog
- Repeated vomiting, diarrhea, or lethargy
- Fever, wounds that will not heal, or signs of infection in the following weeks
Frequently Asked Questions
Frequently Asked Questions
Why are Apoquel poisoning calls increasing?
Pet Poison Helpline reported a rise in toxin calls involving Apoquel (September 2026) as the allergy medication becomes more widely prescribed. It sits in purses, on counters, and in weekly pill organizers, and it smells like food to a dog. Because one bottle holds a month of tablets, a determined chewer can eat far more than a therapeutic dose.
Is Apoquel dangerous for cats?
Oclacitinib is labeled for dogs only. Cats are not routinely given it, and they appear more sensitive — an accidental dose (the classic case is a cat that knocks over the dog's bottle and eats the tablets) warrants a vet call even before symptoms. Watch for vomiting, drooling, lethargy, or wobbliness.
What happens if a dog eats a whole bottle of Apoquel?
Doses above the therapeutic range mainly cause vomiting and diarrhea, but large overdoses suppress the immune system, which can lead to infections days or weeks later. Call a vet or poison hotline with the tablet strength and count eaten — they may recommend decontamination and monitoring. Watch for fever, sores, or worsening skin infections after the initial exposure.
Sources
This entry is reviewed against the following authoritative veterinary sources.
Last reviewed: 2026-10-16