Should we prescribe oral metronidazole or probiotics for acute gastroenteritis in dogs?

PICO question In dogs with acute gastroenteritis, is metronidazole faster, slower, or comparable in resolving clinical signs when compared to probiotic administration?   Clinical bottom line Category of research question Treatment The number and type of study designs reviewed Five studies total, all were blinded, randomised controlled trials Strength of evidence Moderate Outcomes reported The use of probiotics as a treatment for acute, uncomplicated diarrhoea in dogs may improve clinical signs faster when compared to a placebo, but showed no difference when compared directly to metronidazole. Metronidazole, when compared to a placebo, produced mixed results with one study finding that treatment with metronidazole did significantly reduce the time to resolution of diarrhoea, while another study found the difference with placebo was not significant Conclusion Based on the evidence evaluated, the use of oral metronidazole will not decrease time to resolution of clinical signs in cases of acute, uncomplicated diarrhoea in dogs when compared to probiotic administration and thus should not be a first-line treatment in such cases   How to apply this evidence in practice The application of evidence into practice should take into account multiple factors, not limited to: individual clinical expertise, patient’s circumstances and owners’ values, country, location or clinic where you work, the individual case in front of you, the availability of therapies and resources. Knowledge Summaries are a resource to help reinforce or inform decision making. They do not override the responsibility or judgement of the practitioner to do what is best for the animal in their care.