In adult, non-geriatric, dogs with acute onset (<7 days duration) uncomplicated diarrhoea does the addition of metronidazole to a supportive care protocol such as dietary modification or probiotics (excluding other antimicrobials) reduce the time to resolution of diarrhoea compared to supportive care protocols alone?
Clinical bottom line
Category of research question
The number and type of study designs reviewed
Four studies were included in this appraisal. Two prospective, double blinded, placebo controlled clinical trials, one prospective treatment trial and one retrospective longitudinal observational study
Strength of evidence
One study found a shortened duration of clinical signs (by 1.5 days; p = 0.04) in the metronidazole treated group compared to control. However, a separate study found no significant difference between control and metronidazole groups in the regards to resolution of clinical signs.
One study demonstrated a long standing (>28 day) negative impact of metronidazole treatment on gut microbiome with no difference in time to resolution of clinical signs when compared with faecal matter transplant
The current evidence for the superiority of metronidazole compared to supportive treatment alone is weak and at this time there is no evidence-based rationale for its use in cases of uncomplicated, acute, canine diarrhoea. Furthermore, the negative implications of metronidazole on the intestinal microbiome have been found to be long standing (>28 days as a minimum) and should not be discounted by the prescribing clinician
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.