Solensia (frunevetmab) is the first and, as of early 2026, only FDA-approved medication specifically indicated for the control of pain associated with osteoarthritis (OA) in cats. Developed by Zoetis, Solensia is a monoclonal antibody that targets nerve growth factor (NGF), a key protein involved in pain signaling. It is administered as a once-monthly injection at a veterinary clinic.
For decades, cats with arthritis had very few safe, long-term pain management options. NSAIDs carry significant kidney and gastrointestinal risks in cats, and many pain medications approved for dogs are not suitable for feline use. Solensia represents a meaningful advance in feline pain management, offering a targeted approach with a different safety profile than traditional pain medications.
What Is Solensia Used For?
Solensia is used for the control of pain associated with osteoarthritis in cats. Osteoarthritis is a degenerative joint disease that causes chronic pain, stiffness, and reduced mobility. It is far more common in cats than many owners realize — studies suggest that up to 90% of cats over 12 years of age have radiographic evidence of OA, though many go undiagnosed because cats are skilled at hiding pain.
Signs of arthritis pain in cats may include:
- Reluctance to jump onto or down from furniture
- Hesitation going up or down stairs
- Stiffness after resting
- Decreased grooming (matted or unkempt fur, especially on the back)
- Reduced playfulness or activity
- Changes in litter box habits (difficulty getting in or out)
- Increased irritability when handled or touched
- Hiding or social withdrawal
Solensia does not cure osteoarthritis or reverse joint damage. It helps manage pain, which may improve your cat’s comfort, mobility, and quality of life.
How Does Solensia Work?
Solensia is a felinized (cat-specific) monoclonal antibody that targets and neutralizes nerve growth factor (NGF). NGF is a protein that plays a central role in the development and transmission of pain signals, particularly in chronic pain conditions like osteoarthritis.
In OA, damaged joint tissues produce elevated levels of NGF, which sensitizes pain receptors and amplifies pain signals. By binding to NGF and preventing it from activating pain pathways, Solensia reduces the pain signal without relying on anti-inflammatory mechanisms like those of NSAIDs or corticosteroids.
Because Solensia is a felinized antibody (engineered to resemble natural cat antibodies), it is broken down by the body through normal protein metabolism rather than through the liver or kidneys. This is a potential advantage for older cats that may have concurrent kidney or liver disease, though your veterinarian will evaluate your cat’s overall health before recommending Solensia.
Dosage
Solensia is administered by your veterinarian. It is not available for at-home use.
| Parameter | Detail |
|---|---|
| Dose | 1 mg/kg (minimum) |
| Route | Subcutaneous injection (under the skin) |
| Frequency | Once monthly |
| Where given | At your veterinary clinic |
| Weight range | Labeled for cats 5.5 lbs (2.5 kg) and above |
Important notes:
- Your veterinarian will determine the appropriate dose based on your cat’s body weight.
- Solensia comes in a pre-filled syringe for veterinary use.
- Improvement may be gradual. Some cat owners notice changes after the first injection, while others may not see clear improvement until the second or third monthly dose. Your veterinarian may recommend a trial of at least 2-3 monthly injections before assessing whether Solensia is helping your cat.
- If you miss a monthly appointment, contact your veterinarian to reschedule. The pain-relieving effect will diminish as the antibody is cleared from your cat’s system.
How to Give Solensia to Your Cat
Solensia is given exclusively at a veterinary clinic as a subcutaneous injection. You do not need to administer this medication at home. The injection is typically quick and well tolerated by most cats.
What to expect at the appointment:
- The injection is given under the skin, usually between the shoulder blades.
- Most cats tolerate the injection with minimal reaction.
- The appointment is brief; no sedation is required.
- Your veterinarian may combine the visit with a routine wellness check.
Monitoring at home: After each injection, observe your cat over the following days and weeks for:
- Changes in activity level, willingness to jump, and overall mobility
- Grooming habits
- Appetite and general demeanor
- Any unusual signs or behaviors
Keeping a simple log of your cat’s activity and behavior can help you and your veterinarian assess whether Solensia is providing benefit.
Side Effects
In clinical studies, Solensia was generally well tolerated. However, as with any medication, side effects can occur.
| Common Side Effects | Serious Side Effects (Contact Your Vet) |
|---|---|
| Injection site reactions (mild swelling, pain) | Vomiting |
| Mild lethargy after injection | Persistent or severe injection site reactions |
| Mild increase or decrease in appetite | Lameness or worsening pain |
| Signs of allergic reaction (facial swelling, difficulty breathing, hives) | |
| Significant behavioral changes |
Study results: In the FDA pivotal study, 77% of cat owners reported improvement in signs of OA pain after 3 months of Solensia treatment. The most common adverse events reported in studies were vomiting and injection site pain, both of which were generally mild.
Because Solensia is a relatively new medication (FDA-approved in 2022), long-term safety data beyond clinical trial durations is still being gathered. Your veterinarian can discuss the latest safety information and help you weigh the benefits against potential risks for your individual cat.
Drug Interactions
No specific drug interactions with Solensia have been identified in clinical studies. Because Solensia is a biologic (a protein-based antibody) rather than a small-molecule drug, it is not metabolized through the liver’s cytochrome P450 system and is less likely to interact with conventional medications.
However, always inform your veterinarian about all medications, supplements, and treatments your cat is currently receiving. The safety of Solensia used concurrently with other anti-NGF therapies or certain immunosuppressive drugs has not been thoroughly evaluated.
Contraindications
- Do not use in cats with known hypersensitivity to frunevetmab or any component of the formulation.
- The safety of Solensia has not been evaluated in breeding, pregnant, or lactating cats.
- The safety of Solensia in kittens has not been established.
- Solensia has not been evaluated for use in cats with concurrent malignancies (cancer). Because NGF may play a role in certain biological processes beyond pain, discuss any concerns about cancer or other conditions with your veterinarian.
Storage
Solensia is stored and administered at the veterinary clinic. Pet owners do not need to store this medication at home.
- Veterinary storage: Refrigerate at 36-46 degrees F (2-8 degrees C). Do not freeze. Protect from light. Store in original packaging.
Cost & Availability
Solensia is available exclusively through veterinary clinics. It cannot be purchased at pharmacies or online retailers.
| Cost Component | Approximate Range |
|---|---|
| Per injection | $60-$180 (varies by region and clinic) |
| Monthly cost | $60-$180 plus any associated office visit fees |
| Annual cost (12 injections) | $720-$2,160+ |
- Cost varies by geographic location, veterinary clinic, and your cat’s weight.
- Some clinics include a brief exam with each injection visit; others may charge separately.
- Pet insurance may cover part of the cost if your cat has an OA diagnosis. Check with your insurance provider.
- No generic version of Solensia is currently available.
Because Solensia is a biologic therapy, it is generally more expensive than traditional oral pain medications. Your veterinarian can help you consider cost alongside expected benefits and alternative management options (weight management, environmental modifications, physical rehabilitation, and other treatments).
FAQ
Q: How long does it take for Solensia to work? A: Some owners notice improvement within the first week after injection, but results vary. Your veterinarian may recommend a trial of 2-3 monthly injections before fully assessing response. Changes can be subtle at first, since cats often hide pain, so improvements in jumping, grooming, and general activity may be the most noticeable signs.
Q: Can Solensia cure my cat’s arthritis? A: No. Solensia manages pain associated with osteoarthritis but does not reverse joint damage or halt disease progression. It is one component of a comprehensive arthritis management plan that may also include weight management, environmental modifications (ramps, heated beds, low-sided litter boxes), and other therapies as recommended by your veterinarian.
Q: Is Solensia safe for cats with kidney disease? A: Because Solensia is a protein-based biologic that is metabolized through normal protein turnover rather than through the liver or kidneys, it may be an option for cats with concurrent kidney disease. However, your veterinarian should evaluate your cat’s overall health before starting treatment. Discuss any concerns about kidney function with your veterinarian.
Q: My cat seems fine — could it still have arthritis? A: Yes. Cats are well known for masking signs of pain, and arthritis is frequently underdiagnosed in cats. Subtle changes in behavior (less jumping, decreased grooming, reluctance to use stairs, sleeping more) may be signs of chronic pain. If your cat is over 10 years old, ask your veterinarian about screening for osteoarthritis.
Q: Is Solensia related to Librela for dogs? A: Both Solensia and Librela (bedinvetmab) are monoclonal antibodies that target nerve growth factor (NGF) for osteoarthritis pain. They are made by the same manufacturer (Zoetis) and work through a similar mechanism. However, they are species-specific — Solensia is formulated specifically for cats, and Librela is formulated specifically for dogs. They are not interchangeable.
Sources & References
- FDA - Solensia (Frunevetmab) Approval Information
- Zoetis - Solensia Product Information
- Merck Veterinary Manual - Osteoarthritis in Cats
- VCA Animal Hospitals - Arthritis in Cats
- American Association of Feline Practitioners - Chronic Pain and Osteoarthritis
- Journal of Feline Medicine and Surgery - Anti-NGF Antibody Therapy in Cats
This content is for informational purposes only and is not a substitute for professional veterinary advice. Always consult your veterinarian to determine the best pain management plan for your cat.