Reporting adverse events for veterinary medicines

Information on reporting adverse events related to veterinary medicines in the European Union (EU)

EMA and national authorities continuously monitor whether animals that have received a vaccine or medication experience any side effects, also called adverse events. 

This ensures that the benefits of veterinary medicines continue to outweigh their risks.

Anyone can report an unfavourable and unintended event in an animal, person or the environment following the use of a veterinary medicine. 

However, animal health practitioners, or veterinarians, have an essential role to play. They are often the first port of call for animal owners in terms of reporting medicine-related side effects that their animals experience.

How to report adverse events

Select the expandable panels below to read about the steps necessary to report suspected adverse events.

Step 1: Gather information

If you want to report adverse events in animals, you need to include the following information: 

• The animal species, the age, sex, breed, and identification
• Details of the adverse reaction and the veterinary medicine used
• Any other relevant treatments

You are encouraged to provide as much information as possible in the report.

Step 2: Report to the appropriate authority

The appropriate authority can be:

• the national competent authority in your country;
• or the pharmaceutical company listed on the product packaging. 

Make sure to use the reporting format that the appropriate authority requires.

For details on where to report suspected adverse events, see:

• Veterinary product information (QRD) templates: Appendices

Step 3: Provide supporting documentation

Supporting documentation can include: 

• Photographs or videos of the affected animal, if relevant
• Copies of diagnostic reports or test results
• Copy of the product label or packaging, if available

Step 4: Confirm and follow up

After you have submitted your report to the appropriate reporting authority, make sure to: 

• check if you have received a receipt confirmation;
• provide any additional details, if requested;
• continue monitoring your animal's condition. 

What happens after reporting adverse events

Marketing authorisation holders have a legal obligation to continuously monitor adverse event reports.

EudraVigilance Veterinary is the European database that centralises all reports of suspected adverse events in animals.

When marketing authorisation holders identify new risks, competent authorities can take necessary regulatory measures. 

These measures include adding new adverse events or warnings to the product information, and publishing information for animal health practitioners.  

Very rarely, national competent authorities or the European Commission can suspend veterinary medicines or withdraw them from the market until there are no longer safety concerns.

For more information, see:

• EudraVigilance - European database of suspected adverse drug reaction reports
• Medicine evaluation figures: Annual medicine overviews

Frequently asked questions

Select the expandable panels below for frequently asked questions. 

What is an adverse event?

An adverse event is an unfavourable and unintended event in an animal, person or the environment that occurs:

• following the use of a veterinary medicine, including off-label usage;

• or following the use of a human medicine that has been administered to an animal. 

It is also known as side-effect, adverse drug reaction or vaccine failure.

What should I report?

• All suspected adverse events in animals and humans following the use of veterinary medicines, including off-label use; this also refers to adverse events already stated in the product information.

• Any suspicion that a veterinary medicine has not be effective.

• Adverse events in people exposed to veterinary medicines or treated animals.

• Environmental incidents, high product residues in foods and suspected transmission of infectious agents.

• Suspected adverse events in animals after the use of human medicines.

• A suspicion of an adverse event - it does not need to be investigated or confirmed. 

For which animals should I report suspect adverse events?

Report suspected adverse events in all species of animals. 

Should I report lack of efficacy?

Report any observation of lack of efficacy of a veterinary medicine following its administration to an animal.

This is regardless of whether or not it is in accordance with the summary of product characteristics.

Should I report that an animal consumes less water after receiving a veterinary medicine?

Report any unfavourable and unintended reaction to a veterinary medicine in any animal.  

Should I report an adverse event in humans exposed to a veterinary medicine?

Report any noxious reaction in humans exposed to a veterinary medicine. 

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27 August 2026

Page first published; Content has been moved from another webpage as part of a broader content reorganisation