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Frequently Asked Questions

Q. What is pharmacovigilance?

A. Pharmacovigilance is the process of detecting, evaluating, understanding and preventing the adverse effects of medicines. Veterinary pharmacovigilance concerns the safety of veterinary medicines used for the treatment, prevention or diagnosis of disease in animals. The Veterinary Medicines Directorate (VMD) is responsible for veterinary pharmacovigilance in the UK.

Q. What is an adverse effect?

A.  An adverse effect of a medicine (also known as an adverse reaction or adverse event) is an expression which describes harm associated with a given medication. An animal adverse reaction is a harmful and unintended reaction which may be due to exposure to a veterinary medicine administered to an animal at its normal dose. A reaction may occur in an animal undergoing treatment or in an untreated animal in the same household as a treated animal. A human adverse reaction may occur in a person administering a veterinary medicine, or a person exposed to a recently treated animal.

Q. What does veterinary pharmacovigilance cover?

A. It covers adverse reactions in all species of animals to veterinary medicines when administered according to the label instructions. It also covers:

  • Adverse reactions to veterinary medicines in humans.
  • Unauthorised use of authorised veterinary medicines, including misuse and off-label use, i.e. use not in accordance with the manufacturer’s instructions.
  • Lack of efficacy, i.e. when a product which has been used correctly fails to have the expected effect.
  • Incidents in which residues of a product are found in a food animal or its produce after the withdrawal period has been correctly observed.
  • Adverse environmental effects of veterinary medicines.
  • Adverse reactions following the use of human medicines in animals. (N.B. Reactions in humans to human medicines should be reported to the Medicines and Healthcare products Regulatory Agency).
  • Adverse reactions following the use of unauthorised medicines in animals. 

Adverse reactions which are described in the product information should be reported as well as those which are not mentioned, as we need to know about changes in patterns of adverse reactions.

Q. Who can report an adverse reaction?

A. Anyone can send in a report about an adverse reaction to a veterinary medicine which they have experienced or observed.  Members of the public, veterinary surgeons, farmers, doctors and pharmacists are all encouraged to report to the VMD.

Q. Why report adverse reactions to the VMD?

A. An adverse reaction is a reaction to a veterinary medicine that is not expected or wanted. All veterinary medicines can cause adverse reactions, which can range in severity from mild to serious and even life-threatening. Sometimes adverse reactions appear in animals after treatment has stopped, while some reactions might not be discovered until the veterinary medicine has been used in a large number of animals for a long time. That is why it is important for people to report any suspected adverse reactions to the VMD, to enable us to make veterinary medicines safer for all animals.

Q. I want to report an adverse reaction to the VMD. How do I do this?

A. You can make a report:

Q. Is my report confidential?

A. Yes. We ask for contact details so that we can get in touch if we need more information about the adverse reaction. Your contact details will be kept confidential and will not be passed on to anyone outside the VMD without your permission. If you do not want us to contact you, tick the box on the form.

We publish data from information given in reports, but this never includes names or other personal details of the people who made the report.

Q. What happens to my report?

A. We will send an acknowledgment of your report. All the information in the report is recorded on a database and we will examine the report to assess:

  • The severity of the reaction.
  • Whether there have been any previous reports to the same or similar products.
  • Whether any further information is required.
  • What follow-up action is required.

Q. How is the information used to make veterinary medicines safer?

A. All new safety or efficacy issues or sudden changes in the frequency of already known adverse reactions are reviewed three times a year by a group of veterinarians, immunologists, pharmacists, toxicologists and ecotoxicologists from the VMD to find possible previously unidentified hazards and other new information on adverse reactions involving veterinary medicines. We also evaluate information on the safety of veterinary medicines used elsewhere in the EU and in other parts of the world. In addition, all new serious animal safety or efficacy issues and all human reactions are considered three times a year by the Veterinary Products Committee (VPC), a group of independent experts.

If we identify a new possible adverse reaction or find out more about one which is already recognised, we examine this in relation to the overall picture of adverse reactions reported to the product. If the new information changes this picture significantly, we may make a comparison with other veterinary medicines which can be used to treat the same condition and reassess the benefit-risk balance of the product. For a veterinary medicine to be considered safe, its expected benefits should be significantly greater than any associated risks of harmful reactions. Assessment of the benefits and risks of veterinary medicines is necessary in order to determine what action, if any, should be taken to improve their safe use.

Q. What follow-up action can the VMD take?

A. If necessary, we will take action to ensure that a veterinary medicine is used in a way that minimises risk and maximises benefits to the animal being treated. There are a number of possible follow-up actions that can be taken, including:

  • Adding details of a new adverse reaction to the product information.
  • Modifying the instructions for use of the product.
  • Adding a contraindication or warning to the product information about groups of animals in which the product should not be used.
  • Recalling the product or batches of the product from the distribution chain.
  • Withdrawing a product from the market if there is evidence that the risks of the product are greater than its potential benefits.

Q. How can I get more information about veterinary pharmacovigilance?

A. The below leaflets will tell you more about the VMD's pharmacovigilance activities, or you can contact the pharmacovigilance team on 01932 338427.

Last Updated: 20 December 2012

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