Assigning defined daily doses animal: a European multi-country experience for antimicrobial products authorized for usage in pigs.

Objectives: To establish a consensus defined daily dose animal (DDDA) for each active substance (AS) and administration route for porcine veterinary antimicrobial products authorized in four European countries, thus allowing cross-country quantification and comparison of antimicrobial usage data.

Methods: All veterinary antimicrobial products authorized for porcine use in Belgium, France, Germany and Sweden were listed for each administration route. First, separate DDDAs for each product were defined based on the recommended dosing for the main indication. Second, a consensus DDDA was established by taking the mean of the DDDAs for each product within a certain category of AS plus administration route.

Results: One-hundred-and-fifty-nine, 240, 281 and 50 antimicrobial products were licensed in Belgium, France, Germany and Sweden, respectively, in February 2013. Large variations were observed for dosage and treatment duration recommendations between products and between countries for the same ASs. Only 6.8% of feed/water and 29.4% of parenteral AS groups had the same recommended dosage in the four countries.

Conclusions: This study presents a consensus DDDA list for use in the quantification and comparison of antimicrobial consumption. Four major recommendations have been formulated: (i) urgent need for harmonization of authorization and recommended summary of product characteristics (SPC) dosages; (ii) expand the developed preliminary DDDA list to include all authorized veterinary medicinal products in all EU member states and for all (food-producing) animal species; (iii) improved accessibility of country-specific SPC data would be preferable; and (iv) statement of the 'long-acting' duration of a product in the SPC.