If your dog suffers from allergies or skin issues, your vet might suggest Apoquel. However, it’s crucial to be aware of the side effects of this immune-suppressing medication before deciding to use it. How safe is Apoquel really?
Understanding Apoquel for Dogs
Apoquel is commonly prescribed by vets to treat allergies in dogs. It’s promoted as a quick and effective solution for managing both short-term and long-term itching, known as pruritus. Many dog owners report that Apoquel effectively reduces their dogs’ itchiness, often within 4 to 24 hours. But there’s more to consider…
How Apoquel Functions
Apoquel works by targeting kinases in the body, which are compounds that help cells communicate. These kinases—JAK1, JAK2, JAK3, and TKY2—are crucial for preventing tumor formation, regulating growth, producing blood cells, and supporting the immune system. By inhibiting these, Apoquel can reduce allergic reactions but at the cost of compromising your dog’s immune system.
Detailed Role of JAKs
- JAK1 is vital for the constant surveillance within your dog’s body, finding and destroying abnormal cells that have become cancerous before they form tumors. It’s also needed to destroy invading parasites, fungi, bacteria, and viruses.
- JAK2 is central to the production of bone marrow stem cells, which become red and white blood cells and platelets.
- JAK3 helps your dog’s antibody system (B cells) and its killer-cell system (T cells) work properly.
These JAKs communicate with each other to keep your dog’s body healthy. By preventing JAKs from working, Apoquel undermines your dog’s immune system to prevent allergic reactions.
Is Apoquel Safe for Dogs?
A safety study by Apoquel’s manufacturer, Zoetis, showed no fatalities during a 28-day trial. However, post-study findings were concerning:
- One dog was euthanized after 450 days due to fluid buildup.
- Six dogs were euthanized due to suspected cancers, which can spread undetected because of immune suppression.
- Two dogs developed Grade II mast cell tumors after 52 and 91 days.
- One dog developed low-grade B-cell lymphoma after 392 days.
- Two dogs developed apocrine gland adenocarcinoma after 210 and 320 days.
- One dog developed painful oral cancer after 320 days.
While Zoetis reported no fatalities during the initial 7-day study, the continuation phase showed that six dogs had to be withdrawn due to abnormal health events. Approximately 6% of dogs experienced issues within just 30 days. Although the manufacturer claims long-term safety, the study suggests otherwise.
Research Findings
A study published in 2020 looked at medical records of 660 dogs from four veterinary dermatology clinics. Out of 339 dogs who received Apoquel, 67 dogs (16.5%) developed malignancies, including mast cell tumors, lymphoma, and brain tumors.
FDA Warning
The FDA criticized Zoetis for downplaying the drug’s risks in their advertising, using short-term studies to claim minimal side effects. They issued a warning letter about misleading representations of Apoquel’s safety.
Apoquel Safety for Puppies
Apoquel is only approved for use in dogs over 12 months old. This restriction is due to findings from studies that showed younger dogs developed severe infections quickly when administered the drug. For 12-month-old dogs, observed side effects included:
- Papillomas (warts)
- Interdigital furunculosis (cysts) with related dermatitis symptoms
- Edema of feet
- Pneumonia
- Lymphadenopathy (abnormal or swollen lymph nodes) in peripheral nodes
The drug also affects blood cell counts and lymphatic tissue, which can be particularly concerning in younger dogs whose immune systems are still developing.
Important Safety Information:
- Age Restriction: Do not use Apoquel in dogs less than 12 months of age or those with serious infections.
- Infection Risk: Apoquel may increase the chances of developing serious infections and may exacerbate existing parasitic skin infestations or pre-existing cancers.
Understanding Apoquel’s Risks: A Quick Guide
- Cancer Concerns: Apoquel may worsen existing cancers and lead to new growths.
- FDA Warning: Zoetis was reprimanded for misleading advertising.
- Side Effects: Includes skin issues, infections, and digestive problems.
- Rebound Effect: Symptoms can return intensely if Apoquel is stopped suddenly.
Rebound Phenomenon (Withdrawal Issues) Some dogs experience a return of allergy symptoms when taken off Apoquel, known as the “rebound phenomenon.” This can cause intense itching episodes as the immune system reacts strongly after being suppressed.
Conclusion
Long-term use of Apoquel involves significant risks. It’s essential for dog owners to research and consult with veterinarians when considering this medication. If discontinuing, do so gradually under veterinary guidance to avoid severe withdrawal symptoms.
FDA Communication on Apoquel: Key Highlights
The U.S. Food and Drug Administration (FDA) issued a letter to Zoetis, Inc., addressing concerns about misleading marketing practices related to Apoquel (oclacitinib tablet). Here’s what you need to know:
- Misleading Risk Information: The FDA found that Zoetis’ promotional materials misrepresented Apoquel’s safety, falsely suggesting it was safer than steroids without adequate comparative studies. Short-term study results were used to downplay risks, contradicting long-term findings of higher adverse reactions.
- Important Safety Information: Apoquel should not be used in dogs with serious infections or those under 12 months old, as it may increase infection susceptibility and worsen existing cancers. The label advises against combining Apoquel with other systemic immunosuppressants.
- FDA’s Action: The FDA requested Zoetis to cease distributing misleading promotional content and submit a corrective plan within 30 days.
The FDA underscores Zoetis’ responsibility to ensure their marketing materials adhere to legal standards and truthfully represent Apoquel’s risks.
For more details, refer to the FDA Communication on Apoquel.