The Veterinary Medicines Directorate is aware of concerns raised by some dog owners and veterinary professionals about Librela, a treatment for the alleviation of pain associated with osteoarthritis in dogs.

Based on all available evidence and our in-depth analysis, we are satisfied that the overall benefits of Librela continue to outweigh the risks for the vast majority of dogs treated with this medicine. All medicines carry a risk of potential adverse events, and monoclonal  antibody products are no exception.

We take all reports of adverse events seriously. Our pharmacovigilance team continuously reviews safety data for all authorised veterinary medicines, including Librela, to ensure the benefit-risk balance remains positive.
We are independently evaluating reports, assessing new data, and reviewing ongoing and planned safety studies to ensure that the product information adequately represents the latest evidence  available. For example, we recently added the event terms immune-mediated polyarthritis, paresis and paralysis to the product information in January 2026. Details can be found on our Product Information Database and recently published Librela Solution for Injection for Dogs – SPC update – GOV.UK. We will continue to review all evidence as it is reported to us and will make updates to the adverse event information contained in the product information accordingly.

Our in-depth assessment of Librela covers the following specific adverse events: death; arthritis – specifically in relation to more rapid than expected progression of arthritis; and human exposure reports. We have also undertaken routine assessment of reports involving lack of efficacy, recumbency, muscle weakness, lameness and tremor. We will be writing to veterinary professionals to provide detailed information on the outcome of our assessment and to inform them of the latest approved changes to the product information.

Librela was first authorised for use in the UK in November 2020. As with all veterinary medicines, we carefully assess every adverse event report we receive.

We understand the distress that any adverse event can cause to both dogs and their owners. The data shows that the frequency of adverse events reported in the UK following Librela administration is uncommon, occurring in 1 to 10 animals per 1,000 estimated animals treated. Reports of death following Librela administration are rare, occurring in 1 to 10 animals per 10,000 estimated animals treated. Many dogs experience significant improvement in their symptoms following treatment.

It is important to understand that Librela is primarily used in older dogs, many of whom have multiple health conditions and are taking other medications. This makes it more difficult to establish whether adverse events are directly caused by Librela. This complexity is an important factor that veterinary professionals consider when prescribing.

For veterinary professionals, please continue to follow the recommendations in the Summary of Product Characteristics, monitor your patients carefully, and report any adverse events directly to Zoetis.  Dog owners are also encouraged to report adverse events to Zoetis, if you have concerns about your dog’s treatment, speak to your veterinarian and carefully read the Product Information Leaflet which can be found in our  Product Information Database.

The VMD’s role is to protect animal health and welfare. We will continue to monitor Librela closely and will take action if the evidence shows the risks of the product outweigh the benefits.