You can report a bad reaction to an animal medicine or microchip to the Veterinary Medicines Directorate (VMD), eg bad side effects.

Report a bad reaction to an animal medicine in an animal

You can report when a medicine hasn’t worked, or has made your animal unwell.

You’ll be asked for details of:

  • the medicine, including batch number and medical authorisation number if known
  • the animal that was affected, eg species, breed and age
  • when and how the medicine was first given to the animal
  • the symptoms


Report a bad reaction to an animal medicine in a human

You can report a bad reaction you or someone else has had to an animal medicine while using it on an animal, eg a skin allergy.

You’ll be asked for details of:

  • the medicine, including the batch number and medical authorisation number (if you know it)
  • the people affected - and how and when they came into contact with the medicine
  • the symptoms


If you can’t report online

Download and fill in the form for reporting an adverse reaction in either a human or an animal and send it to the address on the form.

Report a bad reaction to a microchip

You can report incidents with animal microchips including:

  • a reaction to the chip being implanted, eg injury, infection or prolonged bleeding
  • if a chip’s moved from where it was implanted or has come out
  • a chip that doesn’t read properly

You’ll need the microchip number to make a report.


Contact VMD

Contact the VMD Pharmacovigilance Team if you have any questions about reporting reactions.

VMD Pharmacovigilance Team adverse.events@vmd.defra.gsi.gov.uk
Telephone: 01932 338427
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