Study objectives: To determine whether prophylactic antibiotics prevent infection in patients with dog bite wounds.
Design: Meta-analysis of published studies.
Methods: A literature search was performed to identify published, randomized trials of prophylactic antibiotics for dog bite wounds. The relative risk for infection in treated patients compared with controls was used as the measure of effect, and a summary relative risk was calculated.
Results: Eight randomized trials were identified. The estimated cumulative incidence of infection in controls was 16%. The relative risk for infection in patients given antibiotics compared with controls was 0.56 (95% confidence interval, 0.38 to 0.82). About 14 patients must be treated to prevent one infection.
Conclusion: Prophylactic antibiotics reduce the incidence of infection in patients with dog bite wounds. The full costs and benefits of antibiotics in this situation are not known. It may be reasonable to limit prophylactic antibiotics to patients with wounds that are at high risk for infection.