is a single dose of prophylactic antibiotics sufficient in patients with acute non-complicated appendicitis?

background: acute appendicitis is one of the most common acute surgery events. its main treatment is surgery. however medical management before and after the surgery has an important impact on the treatment. objective: the aim of study was evaluating the outcomes of single dose and quadruple doses of prophylactic antibiotic therapy in patients with acute non-complicated appendicitis. methods: this randomized double blind clinical trial was carried out on 294 patients in single dose (136 patients) and the quadruple doses (158 patients) groups. in single dose group, a dose of 1g cefazolin + 500mg metronidazole was prescribed intravenously about half an hour before surgery. the quadruple doses group received three more doses after surgery.  two groups were followed for fever, erythema, seroma, wound infection, intra-abdominal abscess formation and readmissions within one month after discharge. results: the mean age of patients was 31±5.14 years. 203(69%) of patients were men while 91(31%) were women. there were no significant statistical differences between groups in age, sex and body mass index (bmi) variables. no significant statistical differences were observed during surgery and hospitalization period between two groups. in the single dose group, wound infection was 8(5.9%), while it was 6(3.8%) in the quadruple doses group; hence, there were no significant statistical differences in this regard. there was no abdominal abscess in groups. there were significant statistical differences regarding erythema, seroma and antibiotics consumption costs between groups. conclusion: a single dose of prophylactic antibiotics is sufficient in patients with acute suppurative non-complicated appendicitis.