Numelvi (Atinvicitinib) for Dogs: Uses and Safety

PetMD’s medications content is written and reviewed by veterinary professionals to answer common questions about how medications work, their side effects, and what species they are prescribed for. This content should not replace advice from your veterinarian. 

What Is Numelvi Used for in Dogs?

Numelvi contains the active ingredient atinvicitinib and is an FDA-approved prescription medication used to control itchy skin (pruritus) associated with allergic dermatitis in dogs 6 months of age and older. 

Numelvi Considerations for Dogs

Before starting Numelvi, tell your veterinarian about your dog's health history and any medications or supplements they take. 

Numelvi should not be used in: 

• Dogs younger than 6 months  
• Dogs with serious infections  
• Pregnant, breeding, or nursing dogs 

Use Numelvi with caution because: 

• It may increase the risk of skin infections, including Demodex mite infestations (demodicosis) or painful infections between the toes (interdigital furunculosis). 
• Benign and malignant tumors have been reported with similar medications.  
• Its safety hasn't been established when used with certain medications, including cyclosporine (which helps manage itching) or glucocorticoids (steroids commonly used to treat allergies). 

How Does Numelvi Work in Dogs?

Numelvi uses a targeted approach to stop your dog's itching. It blocks a protein called Janus kinase (JAK), which sends signals that trigger itch and inflammation, helping break the itch cycle in dogs with allergic dermatitis. 

How Do You Give Numelvi to Dogs?

Give Numelvi exactly as prescribed by your veterinarian. 

• Tablets are available in 4.8 mg, 7.2 mg, 21.6 mg, and 31.6 mg strengths. Your veterinarian will select the correct tablet strength based on your dog's body weight. 
• Give by mouth once every 24 hours with food.  

What Happens If You Miss a Dose of Numelvi? 

If a dose is missed, consult your veterinarian for guidance. 

They will typically advise giving the medication as soon as you remember, unless it’s close to the time for the next scheduled dose. Never administer additional or double doses. 

Numelvi Side Effects in Dogs

Most dogs tolerate Numelvi very well. However, as with any other medication, some side effects can occur. 

While usually mild, some common side effects include: 

• Upset stomach (nausea, vomiting, or diarrhea) 
• Decreased appetite 
• Decreased energy 

Reach out to your veterinarian if these symptoms are severe, don't go away, or seem to be getting worse. 

Contact your veterinarian immediately if you notice: 

• Signs of a possible skin infection (increased itching, redness, or oozing/bleeding sores) 
• Signs of another infection (frequent or painful urination, extreme tiredness, coughing, or a complete lack of appetite) 
• New lumps, or if existing tumors are growing larger 

Your veterinarian may also notice changes in your dog’s routine bloodwork, such as fluctuations in blood cell counts, liver values, or cholesterol levels. Regular blood tests are therefore essential for dogs receiving long-term treatment. 

Human Side Effects 

Numelvi is not for human use.  

Wash your hands after handling the tablets and keep them out of reach of children. 

If someone accidentally swallows Numelvi, seek medical attention or call Poison Control at 800-222-1222. 

Monitoring Your Dog 

No specific monitoring is required while taking Numelvi. However, your veterinarian may recommend routine bloodwork based on your dog's health, other medications, or how long they'll be given the medication. 

At home, monitor your dog for: 

• Less itching and redness (to evaluate how effectively the drug is working) 
• Signs of infection 
• New growths 
• Side effects listed above 

When Should You Call Your Veterinarian? 

Call your veterinarian if you see any of the following, or if you have additional questions or concerns about the use of Numelvi: 

• Severe side effects 
• Your dog’s condition worsens or does not improve 
• You suspect an overdose 

What Happens If a Dog Overdoses on Numelvi?

Dogs generally tolerated doses several times higher than the recommended amount during safety studies. However, higher doses increased the risk of infections such as demodicosis and interdigital furunculosis. 

If you think your dog received too much Numelvi, contact your veterinarian, seek emergency veterinary care, or call an animal poison control center immediately. 

• Pet Poison Helpline: 855-764-7661 
• ASPCA Animal Poison Control: 888-426-4435 

How Should Numelvi Be Stored?

Keep the following storage tips in mind for this medication: 

• Store at room temperature between 59–86 F (15–30 C).  
• Keep tightly closed and out of reach of children and pets.