Librela® and Solensia®: What Pet Owners Should Know

In recent years, two injectable therapies, Librela® for dogs and Solensia® for cats, have been introduced as new tools to help manage osteoarthritis (OA) pain in our pets. These medications are monoclonal antibodies that target nerve growth factor (NGF), a key player in transmitting chronic pain signals. For many families, they’ve offered relief when other treatments seemed limited.

But like all new therapies, it’s important to balance the potential benefits with the risks and to recognize where these medications fit, and where they may not.

How They Work

• Librela® (bedinvetmab) – approved for monthly use in dogs with OA pain
• Solensia® (frunevetmab) – approved for monthly use in cats with OA pain

Both block NGF, interrupting the pain signal from joint disease.

Where They Can Help

• Designed only for OA pain—they are not indicated for neurological conditions (such as degenerative lumbosacral disease).
• Administered by injection, once a month—making them convenient for owners who struggle with daily pills.
• Offer an alternative for pets who cannot tolerate traditional NSAIDs.

Key Cautions and Limitations

While these medications can provide meaningful relief for some pets, there are important cautions to keep in mind:

1. Not to be combined with NSAIDs
   • Librela® and Solensia® should not be used alongside NSAIDs (like carprofen, meloxicam, or firocoxib). The overlap in pain pathways increases the risk of adverse effects.
2. OA use only
   • These drugs are not appropriate for neurological disease, spinal conditions, or other types of pain.
3. Long half-life and cumulative effect
   • Librela® and Solensia® have very long half-lives, on the order of weeks, which is why they are given monthly.
   • This means that if a pet experiences an adverse event, the drug cannot simply be “stopped” like a pill; it remains in the body for weeks to months.
   • With repeated dosing, there is a cumulative effect, and we do not yet fully understand the long-term consequences.
   • For this reason, I only consider using them in extremely select cases, if at all, and I proceed with caution.
4. Concerns about adverse events
   • While many pets tolerate them well, there are growing reports of potential adverse effects, including neurological signs, weakness, or changes in behavior. Ongoing research and pharmacovigilance are investigating these concerns.
   • It’s critical for owners and veterinarians to monitor closely after each injection and report any unusual signs.

What Pet Owners Should Do

• Discuss options with your veterinarian. Librela® and Solensia® may be a good fit in some cases, but they are not the only advanced OA therapies available.
• Watch your pet closely. Any changes in mobility, behavior, or comfort level should be reported immediately.
• Be cautious with combinations. Do not use these alongside NSAIDs or other pain medications unless your veterinarian specifically recommends it.
• Stay informed. Research is ongoing, and as with any new therapy, our understanding of safety continues to evolve.

Final Thoughts

Librela® and Solensia® represent a new class of pain management for dogs and cats with osteoarthritis. But they are not without risks, and their long half-lives and cumulative effect mean that any adverse reaction could linger for weeks or longer.

In my practice, I use these medications only in very select cases, and in many situations, I prefer other established OA treatments with more predictable safety profiles. Further research is clearly warranted to fully understand their long-term safety.

Please read my other posts about these medications before starting them for your pet.

If you are considering Librela® or Solensia® for your pet, have a thoughtful conversation with your veterinarian about the risks, the benefits, and whether another therapy may be a safer or more effective choice.