Care in use of veterinary medicines to avoid drug residues in milk and produce of treated animals

Notice type: Advisory

Date: 01/08/2017


Product name or type:
Veterinary medicines

Target Audience:

Veterinary practitioners, pharmacists and farmers.

Problem Or Issue:

During the authorisation process veterinary medicines are evaluated for the safety of any residues that may remain in meat, milk, eggs and other produce that may be used for human consumption. Only those substances that have been pre-evaluated and approved as safe for consumers by the European Medicines Agency (EMA) are allowed to be used in a veterinary medicine; the HPRA sets the withdrawal period for each individual veterinary medicinal product by reference to the EMA residue benchmark (usually known as the maximum residue limit [MRL]). Where no MRL has been established for milk or eggs, the veterinary medicine cannot be authorised by the HPRA for use in cows producing milk for human consumption or for egg-laying hens. The labelling or package leaflet of the product will clearly state this.

Normally, veterinary practitioners and farmers should choose an appropriate veterinary medicine that is authorised for the species, animal type and condition being treated (e.g. use in milk-producing cows or egg-laying birds, and showing a withdrawal period for milk and eggs). Off-label use of veterinary medicines is restricted by law solely to veterinary practitioners and then only under exceptional conditions in respect of individual animals and in the interests of animal welfare. Indeed, recent scientific opinion advises particular caution in respect of off-label use of antibiotics due to concerns over antimicrobial resistance. Whichever medicine is used, off-label use carries additional risks, including a risk for consumers, and is therefore regulated by the Department of Agriculture, Food and the Marine, in accordance with the animal remedies legislation. Where a veterinary medicine without an MRL for milk or eggs must be used in milk-producing animals or egg-laying birds outside of the terms of their marketing authorisation, the veterinary practitioner must advise on the withdrawal period to be followed, which must, as a minimum, be at least 7 days for milk and eggs, but may often need to be considerably longer.

Background Information Or Related Documents:

The HPRA has previously issued warnings to prescribers and users of veterinary medicines in relation to the potential risks of administering veterinary medicines in dairy-cows.The HPRA considers it timely to once again remind vets and farmers that  inadvertent or intentional off-label use of veterinary medicines without MRLs for milk and/or eggs could result in residues being detected and milk or eggs being rejected as unfit for human consumption, as well as financial and other penalties for those involved.

Actions to be taken: The HPRA would like to remind users of veterinary medicines of the following:

  1. The conditions of use of animal remedies are established following a detailed scientific and evidence-based evaluation of the quality, safety and efficacy of each individual medicine. Deviations from those conditions of use established by the HPRA may invalidate the expected performance of the veterinary medicine under field conditions. In particular, users are reminded to strictly adhere to the withdrawal periods stated on the product labelling and package leaflet.

  2. The use of an animal remedy at a dose above that stated on the product labelling might be expected to prolong the time needed by the animal to clear residues of the medicine beyond that given as the withdrawal period for the product.

  3. Off-label use of veterinary medicines carries additional risks for animal and public health, including that it could give rise to drug residues in the milk or eggs. Such residues have the potential to:

    1. Be harmful for human health;

    2. Result in non-compliance with national residue monitoring standards, and,

    3. Jeopardise the reputation of Irish food on national and export markets.

  4. Farmers are not allowed by law to use veterinary medicines off-label to treat animals or types of animals that are not indicated on the product labelling or package leaflet, save uniquely in situations where they are specifically directed by their veterinary practitioner for the treatment of a particular condition in an individual animal only.

  5. The use of an animal remedy in a milk-producing animal or egg-laying bird which is not an authorised animal that is stated on the product labelling or package leaflet is reserved for veterinary practitioners solely, and then only under particular circumstances where there is no suitable authorised alternative veterinary medicine available for use.

  6. Antibiotics carry particular risks for antimicrobial resistance when used off-label. Therefore, such medicines should never be prescribed or administered:

    1. Without a proper diagnosis,

    2. Purely for practical or economic reasons, or,

    3. For systemic preventative use in groups of animals.

  7. In those exceptional situations where a veterinary practitioner considers it necessary to prescribe or use a veterinary medicine off-label in a cow producing milk for human consumption or in an egg-laying bird, she/he is required to stipulate a withdrawal period that is long enough to ensure consumer safety. The 7 day withdrawal period indicated in the legislation is the minimum to be used, and this is not expected to be sufficient for drugs that have a long half-life. Also, it may not be adequate for those drugs that cross the blood-milk barrier or in other situations (e.g. when another drug is administered concurrently). In these situations the veterinary practitioner should consult with the marketing authorisation holder for the medicine in order to establish an appropriately long withdrawal period. Furthermore, additional residue tests might be needed for these animals in order to ensure the safety of their produce and compliance with the national residue monitoring plan.

  8. The Department of Agriculture, Food and the Marine is the competent authority for regulating the use of veterinary medicines on farm and in the veterinary clinic. For information on the applicable legislation, please contact the Department of Agriculture directly.

  9. Farmers / animal carers in doubt about the use of a veterinary medicine, are advised to consult their veterinary practitioner.


Further Information: Use of veterinary medicines in food-producing animals

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