Overview of Apoquel® for Dogs

Oclacitinib, more commonly known by the brand name Apoquel®, is a prescription medication used to control itching and inflammation associated with allergies in dogs. It belongs to a class of drugs called Janus kinase (JAK) inhibitors, which work by targeting specific cytokines involved in inflammation and pruritus. By interrupting these signaling pathways, oclacitinib helps reduce itching at its source rather than simply masking symptoms.

Unlike corticosteroids or antihistamines, oclacitinib is not classified within either of those drug groups, though its effects can be similar. One of its major advantages is its ability to control itching effectively without many of the long-term side effects commonly associated with steroid use. Clinical studies conducted at 18 veterinary colleges across the United States have demonstrated excellent results, contributing to the drug’s widespread adoption in veterinary medicine.

When oclacitinib was first introduced, availability was a significant challenge, as manufacturing shortages limited distribution to veterinary clinics for more than a year. While supply has since improved, some clinics may still receive limited allotments due to ongoing demand. Despite these challenges, Apoquel® has proven to be a highly effective option for managing allergic itch in dogs.

Oclacitinib is approved and labeled for use in dogs by the U.S. Food and Drug Administration (FDA) and is available only by prescription from a licensed veterinarian.

Brand Names and Approved Use

Oclacitinib is registered for veterinary use in dogs only. The primary veterinary formulation is sold under the brand name Apoquel®. It is not approved for use in cats or other animal species.

Uses of Oclacitinib in Dogs

Oclacitinib is most commonly prescribed to treat allergic conditions that cause itching and inflammation. These include atopic dermatitis (environmental allergies), flea allergy dermatitis, food allergies, and contact allergies. It is often considered a preferred alternative to antihistamines and corticosteroids such as prednisone, dexamethasone, depomedrol, and triamcinolone, particularly for dogs requiring long-term itch control.

How Oclacitinib (Apoquel®) Works and What to Expect

Oclacitinib works by selectively targeting Janus kinase (JAK) enzymes involved in the immune response that causes itching and inflammation in dogs. These enzymes play a key role in transmitting signals from cytokines—chemical messengers that trigger allergic reactions, inflammation, and pruritus. By blocking specific JAK pathways, oclacitinib reduces the signals that cause itching without broadly suppressing the immune system in the way corticosteroids do.

One of the most notable benefits of oclacitinib is how quickly it begins to work. Many dogs experience a noticeable reduction in itching within a few hours of the first dose, with significant improvement often seen within 24 hours. This rapid onset makes Apoquel® especially useful for dogs experiencing acute flare-ups of allergic skin disease.

While oclacitinib is highly effective at controlling itch, it does not cure the underlying cause of allergies. For this reason, veterinarians often recommend using it as part of a broader management plan that may include flea prevention, dietary trials, environmental allergy control, or allergen-specific immunotherapy. Long-term success depends on identifying and managing allergy triggers whenever possible.

Pet owners should also understand that response to treatment can vary. Some dogs require ongoing daily dosing to maintain comfort, while others may transition to intermittent use during allergy seasons. Regular veterinary checkups are important to monitor effectiveness, adjust dosing if needed, and assess for potential side effects over time.

Precautions and Potential Side Effects

When prescribed and monitored by a veterinarian, oclacitinib is generally considered safe and effective. However, as with any medication, side effects may occur. Commonly reported adverse effects include vomiting, diarrhea, decreased appetite, and lethargy. Dogs receiving oclacitinib may also have an increased susceptibility to infections.

Oclacitinib should not be used in dogs with a known hypersensitivity or allergy to the drug. It is also not recommended for dogs under 12 months of age or for dogs with serious infections, as it may increase the risk of conditions such as demodicosis or worsen existing neoplastic diseases. The medication is not approved for use in breeding dogs, pregnant dogs, or lactating dogs.

Caution should be exercised when administering oclacitinib to dogs with underlying conditions such as heart failure, liver disease, or kidney disease. While the drug has been shown to be safe when used alongside antibiotics, vaccines, nonsteroidal anti-inflammatory drugs (NSAIDs), and allergen immunotherapy, it may interact with other medications. Always inform your veterinarian about any drugs or supplements your dog is currently receiving.

How Oclacitinib (Apoquel®) Is Supplied

Oclacitinib is available as an oral tablet in three strengths: 3.6 mg, 5.4 mg, and 16 mg. Tablets are packaged in bottles containing either 20 or 100 tablets. Each tablet is scored and marked with an “S,” “M,” or “L,” corresponding to small, medium, and large tablet sizes, respectively, to assist with accurate dosing.

Apoquel Dosing Chart for Dogs

Oclacitinib should never be administered without veterinary guidance. For the control of itching, the typical dosage is 0.18 to 0.27 mg per pound of body weight (0.4 to 0.6 mg/kg), given orally twice daily for up to 14 days. After this initial period, the dose is usually reduced to once daily for maintenance therapy.

*Dose range based on 0.18–0.27 mg per pound (0.4–0.6 mg/kg).

The medication may be given with or without food and should be stored at room temperature. Hands should be washed after handling Apoquel®, and the medication should be kept out of reach of children.

The length of treatment depends on the condition being treated, your dog’s response to the medication, and whether any side effects develop. Even if your dog appears to improve quickly, it is important to follow the full treatment plan prescribed by your veterinarian unless instructed otherwise, as stopping early may result in a relapse of symptoms.

Always Consult Your Vet

Oclacitinib (Apoquel®) has become a valuable tool in the management of allergic itching in dogs, offering fast relief with fewer side effects than many traditional therapies. If you believe your dog may benefit from this medication, consult your veterinarian to determine whether it is an appropriate option for your pet’s specific condition.