26 randomized controlled trials were included in this systematic review to determine the efficacy of postoperative antibiotic prophylaxis following total knee or hip arthroplasty. This review also looked to also assess the current recommendations by orthopaedic associations on the topic of postoperative antibiotic administration. Evidence from included trials supported the use of perioperative antibiotics, but not postoperative administration. Current recommendations by the American Academy of Orthopaedic Surgeons (AAOS), the British Orthopaedic Association (BOA), and New Zealand Orthopaedic Association (NZOA) suggest postoperative antibiotic administration for a duration of no more than 24-36 hours postoperatively.