Use of veterinary medicines in food-producing animals

Using veterinary medicines

The HPRA authorises veterinary medicines following a detailed examination of quality, safety and efficacy data on the medicine. From the studies submitted by the applicant company, the HPRA establishes the indications for use, contraindications, warnings, withdrawal periods, storage conditions and other pertinent details that are stated on the product labelling and package leaflet.

The medicine should be used in accordance with these instructions, especially if the medicine is intended for use in food-producing animals, due to the risk of harmful residues.

The authorisation process

An application for a marketing authorisation must be submitted to us for evaluation, to see whether it conforms to specified European requirements for quality, safety and efficacy. Under this system, we review information on:

  • The manufacture of the medicine, including raw material quality and process controls,
  • The stability of the product during storage and use,
  • The suitability of the product containers and other packaging materials,
  • The overall product quality and testing carried out,
  • The accuracy and readability of the product labelling and package leaflet,
  • The toxicity of the product,
  • The safety of the product for the animal, user, environment, and in the case of food-producing animals, the consumer,
  • The efficacy of the product for the claimed indications for use.

The risks of use of the product are balanced against the expected benefits. Only when we are satisfied that the product meets the requirements do we grant a marketing authorisation. However, our tasks do not stop there; we continue to monitor the benefit/risk balance throughout the lifetime of use of the product. This monitoring activity is known as pharmacovigilance and includes:

  • Evaluating reports of suspected or unexpected adverse events submitted, including violations of approved residue limits, environmental effects, lack of expected efficacy, off-label use and human adverse reactions.

We also undertake additional measures in order to ensure the veterinary medicines perform as expected, including:

  • Collaborating with colleagues from other European medicines agencies to ensure timely and coordinated regulatory actions, as necessary, to safeguard animal and human health,
  • Reviewing scientific literature, reports of government and international bodies on animal health and consumer protection for potential impact on the safety and efficacy of veterinary medicines authorised in Ireland,
  • Reviewing EU and international developments on antimicrobial resistance,
  • Collecting information on the usage of veterinary antibiotics in Ireland,
  • Implementing decisions of veterinary medicines which are required by the EU Commission in order to safeguard animal health and welfare in Member States.

Understanding the conditions under which veterinary medicines perform

Because veterinary medicines are authorised under specific and controlled conditions, new information may come to light when the products are used widely under field conditions. This is the reason why pharmacovigilance is so important and why adverse reactions should be reported to us.

We would like to remind users of veterinary medicines of the following:

  • The instructions for use of veterinary medicines are based on scientific evidence from studies conducted using the medicine. Deviations from those conditions of use established by the HPRA such as using a higher dosage will invalidate the performance of the product under field conditions. In particular, users are reminded to strictly adhere to the withdrawal periods stated on the product information,
  • The use of a veterinary medicine at a dose above that stated on the product label is likely to prolong the time needed by the animal to clear residues of the medicine beyond that given as the withdrawal period for the product,
  • Where a product is used in a dry-cow and that animal calves early, the withdrawal period to be observed should follow the instructions for use given on the product, that is, an adjustment to take into account the normal period before calving plus the relevant withdrawal period following calving,
  • The administration to an animal of different veterinary medicines at the same time (or within a short period) could result in interactions between the individual medicines. In particular, the withdrawal periods might not be sufficient in situations where two or more drugs follow the same metabolic and elimination pathways from the animal,
  • Consult your veterinary practitioner, pharmacist or licensed retailer regarding the use of veterinary medicines,
  • Store veterinary medicines at the conditions specified on the product container. If products are not stored correctly, they are likely to degrade and may be harmful to the animal,
  • Keep veterinary medicines out of sight and reach of children,
  • In the case of medicines used in food-producing animals, ensure that the Animal Medicines Record is updated on each occasion that a veterinary medicine is administered.