Prevention of post-operative infection in appendicectomy by single dose intravenous metronidazole. An open prospective randomised study.

In an open prospective randomized study of appendicectomy, single-dose (1 g) intravenous metronidazole prophylaxis (and continued metronidazole plus nalidixic acid in perforated appendices) resulted in a lower overall post-operative infection rate (1.4%) than no prophylaxis and doxycycline therapy in the case of perforation (16%, p less than 0.025). In patients with an unperforated appendix no infections occurred after single-dose metronidazole prophylaxis as opposed to 8.2% infections in untreated controls (p less than 0.025).