[Off-label use of antibiotics in equine medicine - an online survey in Germany].

Since 28.01.2022, veterinary medicinal products must be used in accordance with the conditions of authorization (Regulation (EU) 2019/6, Article 106). This entails further restrictions on therapeutic freedom, e. g., with regard to dose deviations. To date, there is no data available in equine medicine on the scope of off-label use as any use deviating from the expert information for antibiotics, on the basis of which the feasibility of implementing the new regulations in Germany can be assessed.To collect data on the off-label use of antibiotics, a Germany-wide anonymous online survey was therefore conducted as a quantitative cross-sectional study, which included up to 105 questions. The survey was preceded by expert interviews and pilot surveys.A total of 111 equine veterinarians answered the survey in full. 88.3% (98/111) stated that they had used antibiotics off-label. Enrofloxacin, marbofloxacin, broad-spectrum cephalosporins, doxycycline and metronidazole were frequently repurposed. Approved drugs for horse such as gentamicin, potentiated sulfonamides, benzylpenicillin-procaine and oxytetracycline were also used off-label, often with regard to indication, dose interval and treatment duration. Antibiotics were usually used in higher doses, rarely prophylactically or for non-antibacterial purposes. Popular combinations were gentamicin with benzylpenicillin or with amoxicillin. Human medical antibiotics were rarely used.As this survey confirms, there is a frequent need for repurposing of antibiotics according to animal species and indication in equine medicine, which should be taken into account in future further regulations and the revision of the positive list. In many cases, special conditions in the infection process justify the off-label use of approved preparations for horses. This survey indicates that some dose revisions are to be recommended for antibiotics that have been used for decades and are approved as medicinal products for horses. As there are few financial incentives for pharmaceutical companies to do so, the creation of therapy guidelines for certain indications in horses could alternatively contribute to greater certainty in equine practice with regard to the justification of off-label use.