Oclacitinib
Oclacitinib maleate
Also known as: Apoquel · PF-03394197
Reviewed by the VetSheet Veterinary TeamUpdated Apr 5, 2026Evidence-based veterinary reference
Audited v13 dosing evidence
Structured calculator evidenceFeline atopic skin syndrome (FASS, formerly nonflea-, nonfood-induced hypersensitivity dermatitis [NFNFIHD]) (extra-label)
- q12-24h
NA
Governing clinical context (2)
- ■ Oclacitinib may be administered with or without food. If your animal vomits or acts sick after a dose, try administering the medicine with some food. If there is no improvement, discontinue the medication and contact your veterinarian.
- Store tablets at room temperature (20°C-25°C [68°F-77°F]). Excursions are allowed between 15°C-40°C (59°F-104°F).
Doses are a clinical reference for licensed veterinary professionals. Always confirm against the current label and the individual patient.
Overview
Oclacitinib is a targeted immunomodulatory and antipruritic medication used primarily in veterinary medicine to manage pruritus (itching) associated with allergic dermatitis and to control atopic dermatitis in dogs.
Clinical Warning: Oclacitinib modulates the immune system and may increase susceptibility to infections (e.g., demodicosis, pyoderma) or exacerbate pre-existing neoplastic conditions. It is contraindicated in dogs under 12 months of age due to an increased risk of severe infections.
Clinical Pearl: Oclacitinib provides rapid relief from itching, often working as quickly as corticosteroids (within 4-24 hours), but without the polyuria/polydipsia and long-term metabolic side effects typically associated with glucocorticoids. While the provided monograph does not specify dosing, standard veterinary practice typically initiates therapy at 0.4-0.6 mg/kg twice daily for up to 14 days, followed by once-daily maintenance.
Mechanism of action
Oclacitinib is a targeted enzyme inhibitor that specifically inhibits Janus-kinases (JAK), with a pronounced selectivity for JAK1 and, to a lesser extent, JAK3.
By blocking these enzymes, oclacitinib prevents the signal transduction of a variety of cytokines dependent on JAK1/JAK3 pathways. Most notably, it inhibits Interleukin-31 (IL-31), a key pruritogenic (itch-inducing) cytokine in dogs.
Pathway: Cytokine binds to receptor → JAK1/JAK3 activation is blocked → STAT proteins are not phosphorylated → Pro-inflammatory and pruritogenic gene transcription is halted.
Safety & warnings
Contraindications
- Dogs less than 12 months of age
- Dogs weighing less than 3 kg
- Dogs with severe systemic infections
- Breeding, pregnant, or lactating dogs
- Dogs with evidence of immune suppression (e.g., hyperadrenocorticism)
- Dogs with a history of progressive malignant neoplasia
Adverse effects
- Gastrointestinal upset (vomiting, diarrhea, anorexia)
- Lethargy
- Increased susceptibility to infections (e.g., pyoderma, otitis, demodicosis, pneumonia)
- Transient decreases in leukocytes and serum globulins
- Potential exacerbation of neoplastic conditions
- Histiocytomas or papillomas (benign skin masses)
Precautions
Use with caution in dogs with a history of recurrent infections or neoplasia. Routine monitoring for the development of infections (skin, ears, systemic) and abnormal growths is essential.
Note: Oclacitinib is not approved for use in cats, and its safety and efficacy profile in felines is not fully established, though it is sometimes used off-label by dermatologists.
Drug interactions
Increased risk of immunosuppression and secondary infections.
Increased risk of profound immunosuppression.
Potential for decreased vaccine efficacy or vaccine-induced illness due to immunomodulation.
Monitoring
- Baseline CBC, serum biochemistry, and urinalysis
- Periodic bloodwork (e.g., every 6-12 months) for dogs on long-term therapy
- Monitor for new or worsening skin, ear, or systemic infections
- Monitor for the development of cutaneous or systemic neoplastic lesions
Pharmacokinetics
Half-life
Absorption
Rapidly and well absorbed following oral administration. Peak plasma concentrations (Tmax) are reached in approximately 1 hour. Absolute bioavailability is high (approx. 89%).
Distribution
Low plasma protein binding (approx. 66%). Volume of distribution is roughly 0.9 L/kg.
Metabolism
Metabolized extensively in the liver by multiple cytochrome P450 enzymes.
Elimination
Clearance is primarily via hepatic metabolism, with metabolites excreted in urine and feces.
Overdose
Overdoses up to 3-5 times the therapeutic dose are generally well tolerated but may increase the frequency and severity of expected side effects, particularly gastrointestinal distress (vomiting, diarrhea), lethargy, and localized alopecia or skin thickening. Chronic massive overdose increases the risk of severe immunosuppression and secondary infections. Treatment is supportive and symptomatic, as there is no specific antidote.
Available products
Formulations
- 3.6 mg oral tablet
- 5.4 mg oral tablet
- 16 mg oral tablet
Veterinary
- Apoquel 3.6 mg film-coated tablets
- Apoquel 5.4 mg film-coated tablets
- Apoquel 16 mg film-coated tablets
- Apoquel chewable tablets (various strengths)
Regulatory status
Approved for dogs 12 months of age and older.
Classified as POM-V (Prescription Only Medicine - Veterinary).
Classified as POM-V.
No regulatory data for: 🇭🇰 HK · 🇹🇼 TW · 🇯🇵 JP · 🇰🇷 KR · 🇦🇺 AU
Storage & stability
Store at controlled room temperature between 20°C and 25°C (68°F - 77°F). Keep in the original packaging to protect from moisture and light. Half-tablets should be placed back in the blister pack and used within 3 days.
Client information
Oclacitinib (Apoquel) is a fast-acting medication used to stop your dog's itching and reduce skin inflammation.
- Administration: Can be given with or without food. If vomiting occurs, try giving it with a small meal.
- What to watch for: Monitor your dog for vomiting, diarrhea, or lethargy. Because this drug changes how the immune system responds, watch closely for signs of new infections (like ear infections, skin bumps, or coughing) and report them to your vet.
- Lumps and bumps: Check your dog's skin regularly for any new lumps or warts and point them out at your next vet visit.
- Do not use in: Puppies under 1 year of age, or pregnant/nursing dogs.
- Handling: Wash your hands after handling the tablets.
VetSheet drug reference is intended for licensed veterinary professionals as a clinical decision-support aid, not a substitute for professional judgement or the manufacturer’s current label.