Advice on impacts of using antimicrobials in animals

The European Medicines Agency (EMA) is involved in monitoring and evaluating the risks of using antibiotics in animals. It has looked in particular at the risk of the development of antimicrobial resistance in animals and of the possible transmission of resistance to humans.

EMA is supporting the European Commission's One Health Action Plan against Antimicrobial Resistance.

The European Commission requested scientific advice from EMA in April 2013 on the impact on public health and animal health of using antibiotics in animals and measures to manage the possible risk to humans. The request was structured in the form of four questions:

• Reducing the use of antimicrobial agents in animal husbandry

The Commission's first question concerned the use in animals of 'old' antibiotics or new antibiotics belonging to 'old' classes of antibiotics that have been re-introduced or newly used to treat multidrug-resistant infections, with a particular focus on colistin and tigecycline, two antibiotics that have become life-saving treatments for patients infected by multidrug-resistant bacteria.

In response, EMA's Antimicrobial Advice Ad Hoc Expert Group (AMEG) concluded that:

• maintaining the use of colistin in animals was appropriate, with additional monitoring of off-label use and restrictions on indications to therapy or metaphylaxis and removing all indications for prophylactic use in order to minimise any potential risk associated with a broader use;
• glycylcycline use in animals should remain restricted, due to evidence from human use that tigecycline resistance emerges rapidly.

For more information, see:

In 2016 AMEG revised its 2013 advice on the use of colistin in animals on request of the European Commission, following the discovery of a gene (called mcr-1) that causes bacteria to become resistant to colistin.

The updated recommendation advises that:

• European Union (EU) Member States should minimise sales of colistin for use in animals, to achieve a 65% reduction in EU-wide sales;
• colistin be added to a more critical category of medicines, reserved for treating clinical conditions for which there are no effective alternative treatments.

EMA published its updated advice in July 2016, after the CVMP and CHMP endorsed the AMEG opinion. This advice took account of a public consultation and an open call for scientific data.

For more information, see:

The Commission's second, third and fourth questions concerned:

• the merits or otherwise of classifying antimicrobials considered critically important for humans into different categories with respect to their recommended use in animals;
• the potential impact of authorising new antimicrobials or classes of antimicrobials, for use in animals on the treatment of resistant bacteria in humans;
• risk mitigation measures for antimicrobials that are already authorised for use in veterinary medicine and are considered as critically important for humans.

EMA published its response in December 2014, following endorsement by the CVMP and CHMP and input from a public consultation. EMA's advice included:

• strengthening antimicrobial resistance risk assessment in the evaluation of marketing-authorisation applications for new antimicrobials, particularly if intended for use in food-producing animals;
• improved reporting on 'off label' use in animals of antimicrobials authorised in humans for use against multi-drug resistant infections;
• further risk profiling of certain classes of antibiotics with respect to their use in animals.

For more information, see:

• Initial stakeholder consultation exercise and data sharing

In July 2017, the European Commission requested EMA to update the AMEG categorisation of antibiotics and to further elaborate on the proposed preliminary risk profiling of new antimicrobials (previously known as 'early hazard characterisation').

• Request for an update of the advice on the impact on public health and animal health of the use of antibiotics in animals (categorisation of antimicrobials and early hazard characterisation)

On 28 January 2020, EMA published the updated AMEG categorisation of antibiotics. The updated categorisation includes new classes of antibiotics and takes account of the need to use antibiotics in animals versus the risk of antimicrobial resistance to public health.

There are four categories of antibiotics:

• category A ('Avoid') includes antibiotics currently not authorised for veterinary use. These medicines cannot be used in food-producing animals and should only be given to pets under exceptional circumstances;
• category B ('Restrict') refers to quinolones, third- and fourth-generation cephalosporins and polymyxins. These are critically important in human medicine and their use in animals should be restricted;
• category C ('Caution') covers antibiotics for which alternatives for human use generally exist, but only few alternatives are available in certain veterinary indications. They should only be used when there are no suitable antibiotics in category D;
• category D ('Prudence') covers antibiotics that may be used in animals in a prudent manner. Group treatment should be restricted to situations where individual treatment is not feasible.

An infographic provides a table displaying all available classes of antibiotics in their corresponding risk categories aims to support veterinarians in their choice of antibiotic. 

The updated categorisation takes account of a public consultation.

For more information see:

•   Overview of comments received on 'Answer to the request from the EC for updating the scientific advice on the impact on public health and animal health of the use of antibiotics in animals - Categorisation of antibiotics

Other related information:

• Divergent position by individual CVMP and CHMP members on certain aspects of the advice
• Webinar on EMA’s categorisation of antibiotics used in animals (23/06/2021)

Preliminary risk profiling occurs at an early stage in the development of new antimicrobial veterinary medicines and considers the risk to public health of antimicrobial resistance and the need to implement risk management measures.

On 10 July 2019, EMA published the finalised scientific advice of AMEG on the preliminary risk profiling for new antimicrobial veterinary medicinal productsfollowing a public consultation.

For an overview of the comments received during the public consultation, see: