A medication widely used to help dogs manage arthritis pain is now under increased scrutiny after U.S. regulators alerted veterinarians to reports of serious adverse reactions associated with the treatment.
The U.S. Food and Drug Administration (FDA) has issued a warning regarding Librela, an injectable medication prescribed to dogs suffering from osteoarthritis. While the drug has helped many pets live more comfortably with chronic joint pain, the agency says a growing number of reports have linked the treatment to severe health complications in some animals.
The FDA’s latest communication has sparked concern among pet owners, particularly those whose dogs rely on the medication to maintain mobility and quality of life.
What Is Librela?
Librela, also known by its scientific name bedinvetmab, is a monoclonal antibody therapy designed specifically for dogs experiencing osteoarthritis pain. Developed by the animal health company Zoetis, the treatment is administered through monthly injections and works by targeting pain signals associated with joint disease.
The drug received FDA approval in May 2023 and was recognized as the first monoclonal antibody treatment of its kind for canine osteoarthritis after regulators determined it was safe and effective for its intended use.
Since its launch, Librela has become a popular option among veterinarians seeking alternatives to traditional pain medications.
Serious Side Effects Reported
The FDA’s Center for Veterinary Medicine reviewed adverse event reports submitted between May 2023 and March 2024. According to the agency’s findings, several concerning health issues were reported in dogs that had received Librela injections.
Reported complications included:
- Loss of muscle coordination (ataxia)
- Reduced appetite
- Severe lethargy
- Seizures
- Partial muscle weakness
- Difficulty standing or remaining upright
- Urinary incontinence
- Excessive urination
- Increased thirst
The agency noted that some cases resulted in death, including situations where euthanasia was chosen after the dog’s condition deteriorated significantly.
While the reports do not automatically prove that Librela directly caused every adverse event, regulators believe the number and severity of cases warrant closer monitoring and increased awareness among veterinary professionals.
Zoetis Responds to FDA Findings
In response to the FDA’s review, Zoetis stated that it is actively evaluating new safety information and continuing to monitor reports related to the medication.
According to the company’s Chief Medical Officer, veterinarians should ensure that osteoarthritis is accurately diagnosed before prescribing Librela, as the drug is approved specifically for managing pain associated with that condition.
The company emphasized that it takes all reports seriously and remains engaged in ongoing safety assessments.
What Dog Owners Should Watch For
Experts advise pet parents whose dogs receive Librela injections to closely monitor their pets following treatment.
Any unusual changes—including weakness, loss of coordination, appetite loss, seizures, increased thirst, accidents in the house, or other concerning symptoms—should be reported to a veterinarian as soon as possible. Early intervention may help identify whether the symptoms are related to the medication or another underlying health issue.
Veterinarians remain the best source of guidance when deciding whether Librela remains the right treatment option for a particular dog.
How Adverse Reactions Can Be Reported
Because Librela is a prescription veterinary medication, the FDA encourages pet owners who notice potential side effects to contact their veterinarian immediately.
Veterinarians can submit adverse event reports directly to Zoetis, which is required to forward those reports to the FDA. They may also report incidents directly to the FDA’s veterinary monitoring system.
These reports play a critical role in helping regulators identify safety trends and determine whether additional action is necessary.
Balancing Benefits and Risks
For many dogs battling osteoarthritis, Librela has provided meaningful relief from chronic pain and improved mobility. However, the FDA’s latest warning serves as an important reminder that even innovative treatments can carry risks.
As more safety data becomes available, veterinarians and pet owners are being urged to stay informed, monitor dogs closely after treatment, and discuss any concerns promptly. The ongoing review of Librela’s safety profile will likely remain a key topic within the veterinary community as regulators continue to evaluate new reports.

