12 Dec 2025
A study has found an “essential” antibiotic is frequently being used to treat dogs and cats, despite existing guidelines.
Allister Webb
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More than four in 10 vets have admitted using an “essential” antibiotic to treat a dog or cat in contravention of current guidance, a new study has found.
The paper, published in the Journal of Small Animal Practice, has prompted calls for reform to address what one of its authors described as “alarming” findings.
The analysis focused on use of metronidazole, which the paper described as the “most commonly prescribed antimicrobial for gastrointestinal disease”.
A total of 138 vets, most of whom practice in the UK, responded to the study with details of 332 cases treated with the drug.
It found that metronidazole was chosen to treat patients “exclusively for non-antimicrobial targeted therapy” in 42% of cases, despite recommendations that such an approach would rarely be justified.
Nearly three-quarters (74%) of participants also reported including at least one non-antimicrobial reason for using the drug, while 19% said they had selected it based on an earlier success.
The study team, led by clinicians from Davies Veterinary Specialists in Bedfordshire and the Willows Veterinary Centre, Solihull alongside RVC researchers, acknowledged the findings were in line with those of other studies which suggested many vets regarded the drug as a “multi-purpose medication”.
But they warned a reliance on what was described as “anecdotal reasoning” risked contributing to the development of resistance.
Lead author Justin Ng said: “These insights are alarming given that such practices frequently deviate from current antimicrobial use guidelines, potentially contributing to ongoing challenges with antimicrobial resistance and adverse effects on gastrointestinal health.”
The findings emerged only weeks after the RUMA group announced it was targeting a 30% reduction in antimicrobial use in dogs and cats by 2030.
Although owner expectations were also found to have influenced selection in some (9%) cases, the paper argued greater education and advocation of non-prescription treatment forms were necessary.
The authors also stressed metronidazole is on the WSAVA’s list of essential medications and is only indicated for treatment of microaerophillc and anaerobic microorganisms.
