Background: Appendectomy intra-abdominal is the most frequently performed emergency surgery. This study was conducted to determine the role of postoperative antibiotics in reducing surgical site infections (SSIs) and abscess formation after open appendectomy.

Methods: In the Department of Surgery, Shahid Beheshti Hospital, Babol, Iran, from October 2013 to October 2014 one hundred and fifty two patients, who underwent appendectomy for nonperforated appendicitis (NPA) and fulfilled the selection criteria, were randomized into two groups. Group A patients received a single dose of preoperative antibiotics (ceftriaxone and metronidazole) and group B patients received the same regimen, in addition, antibiotics were administered 24 hours postoperatively. Patients of both groups were followed-up for 30 days to assess the postoperative infectious complications.

Results: Both groups comprised 76 patients, as well both groups were compared in baseline characteristics. Statistically, there was no significant difference in rates of SSIs between both groups. None of the patients developed intra-abdominal collection.

Conclusion: Single dose of preoperative antibiotics (ceftriaxone and metronidazole) was sufficient in reducing SSIs after appendectomy for NPA. Postoperative antibiotics did not add an appreciable clinical benefit in these patients.