Reviewed October 30, 2026 · Research-use information
the short answer
Librela is an FDA-approved monthly injection for canine osteoarthritis pain. In the FDA-labeled field studies, common reactions included urinary tract infection, bacterial skin infection, dermatitis, and increased BUN. Post-approval reports include neurological signs such as ataxia, seizures, paresis, and paralysis, plus vomiting, diarrhea, lethargy, and incontinence; some deaths have been reported. Labeled rates and voluntary reports are not the same. Call your vet for any change.
| Reaction type | What the label says | What it means |
|---|---|---|
| Common labeled study reactions | Urinary tract infection, bacterial skin infection, dermatitis, increased BUN | Observed in controlled field studies; not a complete list |
| Other labeled study events | Lethargy, vomiting, anorexia, lameness, cough | Also reported in the labeled studies |
| Post-approval neurological | Ataxia, seizures, paresis, proprioception deficits, paralysis | Voluntary reports; frequency cannot be reliably estimated |
| Post-approval general, GI, urinary | Anorexia, lethargy, recumbency; vomiting, diarrhea; increased drinking, incontinence | Voluntary reports; causality is not established |
| Serious outcomes | Death or euthanasia reported as an outcome | Report to your vet and FDA; not proof of causation |
Labeled study events and post-approval reports are different kinds of evidence. Reviewed October 30, 2026.
Start with the status
Librela is bedinvetmab, an FDA-approved monoclonal antibody for the control of pain associated with osteoarthritis in dogs. It is given by a veterinarian as a once-monthly subcutaneous injection, and the dose is weight-based. It is not an at-home product, and it is not a cure for arthritis. The label is the right place to start because it separates what was seen in controlled field studies from what has been reported after approval.
What the labeled studies found
In the US field study, urinary tract infection was reported in 11.1% of Librela-treated dogs versus 8.0% of controls; bacterial skin infection in 8.1% versus 6.6%; and dermatitis in 7.4% versus 5.8%. The European field study listed increased blood urea nitrogen in 13.8% versus 4.9%, plus lethargy, vomiting, anorexia, lameness, and cough. Those are labeled study events, not a complete side-effect list, and the numbers are not a prediction for your dog.
What post-approval reports add
The FDA label's 2025 post-approval section lists neurological signs including ataxia, seizures, paresis, proprioception deficits, and paralysis; general signs including anorexia, lethargy, and recumbency; urinary signs including increased drinking and incontinence; gastrointestinal signs including vomiting and diarrhea; and musculoskeletal signs including weakness, tremors, and lameness. It says death, including euthanasia, has been reported as an outcome. These are voluntary reports: not all events are reported, and causation cannot be established from them.
The sponsor's reporting rate
Zoetis says post-approval adverse events have been reported globally at a rate between 1 and 10 per 10,000 doses distributed, with no single category higher than 10 per 10,000. That is a sponsor-reported rate for all adverse events, not a rate for neurological events specifically, and it depends on voluntary reporting. It is useful context, not a guarantee. The FDA label's warning about serious reactions, including death or euthanasia, still stands.
The signs that need a call
Call your vet for balance problems, trouble walking, weakness, trouble standing, seizures, increased drinking or urinating, loss of bladder control, vomiting, diarrhea, or a change in appetite or energy. Treat facial swelling, trouble breathing, collapse, or a seizure as an emergency. Do not wait for the next monthly injection to report a new neurological sign. A phone call is cheaper than a crisis.
Do not stop Librela on your own
Librela is prescribed pain control. Stopping it without your vet can leave pain untreated, and changing the schedule is not an owner decision. If you are worried about a side effect, call the clinic, describe the sign and when it started, and ask what to do next. Report the event to your vet and to the FDA's veterinary adverse-event system. A report does not prove causation, but it is how the post-approval record gets better.
What we do not claim
- We do not claim Librela is risk-free or right for every dog.
- We do not claim a post-approval report proves the drug caused the event.
- We do not claim the labeled study rates apply to every dog.
- We do not claim you should stop Librela without your vet.
Sources
Reviewed October 30, 2026. These are the sources we used for this page. Dollar figures, where present, are estimates from the named source, not quotes.
- FDA: Librela package insertFDA-approved labeling for bedinvetmab injection; labeled and post-approval adverse events.
- Zoetis Petcare: LibrelaSponsor page; post-approval reporting rate and common study side effects.
- VIN Veterinary Partner: Bedinvetmab (Librela)Revised February 13, 2025. Prescription-only, clinic-administered monthly injection; post-approval adverse events.
Questions owners ask
What are the most common Librela side effects in dogs?
In the FDA-labeled field studies, common reactions included urinary tract infection, bacterial skin infection, dermatitis, and increased BUN. Post-approval reports add neurological, gastrointestinal, urinary, and general signs. The label is the best source for the full list.
Are neurological side effects from Librela common?
The FDA label lists ataxia, seizures, paresis, proprioception deficits, and paralysis as post-approval reports, but voluntary reporting cannot give a reliable frequency. Zoetis reports all post-approval adverse events globally at 1 to 10 per 10,000 doses, not a neurological-specific rate.
Should I stop Librela if my dog has a reaction?
Call your vet first. Do not stop or change a prescribed pain medication on your own. The vet can assess the sign, decide whether it is related, and adjust the plan.
How do I report a Librela side effect?
Tell your vet and report it to the FDA's veterinary adverse-event system. Zoetis also accepts reports. A report does not prove causation, but it adds to the safety record.