Outpatient parenteral antimicrobial therapy with ceftriaxone for acute tonsillopharyngitis: efficacy, patient satisfaction, cost effectiveness, and safety Samah Al Alawi,1 Somaya Abdulkarim,1 Hazem Elhennawy,1 Anwar Al-Mansoor,2 Ahmed Al Ansari3,4,5 1Department of Family Medicine, 2Department of Dietetics and Nutrition, 3Training and Education Department, Bahrain Defence Force Hospital, Riffa, 4Arabian Gulf University, Manama, 5Royal College of Surgeons of Ireland, Busaiteen, Kingdom of Bahrain Background: Outpatient parenteral antimicrobial therapy (OPAT) is the administration of intravenous antimicrobial therapy to patients in an outpatient setting. It may be used for patients who have infections that require parenteral treatment but who are otherwise stable enough to not require admission as inpatients. Objective: We aimed to review the treatment of patients with acute tonsillopharyngitis at the OPAT health care clinic in the Bahrain Defense Force Royal Medical Services (BDF-RMS), with regard to efficacy, patient satisfaction, cost effectiveness, and safety. Methods: A retrospective case notes review was conducted for all patients admitted to the OPAT clinic in the BDF-RMS with acute tonsillopharyngitis treated with ceftriaxone, between March 2012 and March 2014. Results: In the period between March 2012 and March 2014, 97 patients with acute tonsillopharyngitis were treated with ceftriaxone for a minimum of 3 days at the OPAT clinic. In total, 94.8% of patients completed the prescribed course of ceftriaxone. Total cure was achieved in 89.7% of patients. Usage of the OPAT clinic led to cost savings of 10,693 BD, while total bed days saved were 301 over the 2-year period examined by this study. Participants in the program expressed high satisfaction rates, and the average (± standard deviation) score on a patient satisfaction survey was 4.41 (± 0.31) out of a total of 5. This study highlights the efficacy, patient satisfaction, cost effectiveness, and safety of the OPAT clinic service for the treatment of acute tonsillopharyngitis with ceftriaxone. We found a 45.5% drop in admission rate for acute tonsillopharyngitis after starting the OPAT service clinic and that 301 bed days were saved through this treatment. Conclusion: This study showed that the management of acute tonsillopharyngitis with ceftriaxone in the OPAT clinic is safe, clinically effective, and cost effective, with low rates of complications/readmissions and high levels of patient satisfaction. Keywords: OPAT, ceftriaxone, tonsillopharyngitis