From the Guidelines
For adults with acute appendicitis, the recommended antibiotic regimen includes intravenous ertapenem (1g daily) for 1-3 days, followed by oral antibiotics like amoxicillin-clavulanate (875/125mg twice daily) for a total 7-10 day course, as this regimen has been shown to be effective in treating the infection and reducing morbidity and mortality 1.
Key Considerations
- The choice of antibiotic should be based on local microbiologic data, cost advantage, allergies, and formulary availability, as well as the severity of the infection and the presence of any complications 1.
- For patients with complicated appendicitis, postoperative broad-spectrum antibiotics are suggested, especially if complete source control has not been achieved, and discontinuation of antibiotics after 24 hours seems safe and is associated with shorter length of hospital stay and lower costs 1.
- The optimal duration of antibiotic therapy is 3-5 days for adult patients with complicated appendicitis who have undergone adequate source control, as longer courses do not prevent surgical site infections (SSI) and may contribute to antibiotic resistance 1.
Antibiotic Options
- Other antibiotic options for acute appendicitis include:
- Ticarcillin-clavulanate
- Cefoxitin
- Moxifloxacin
- Tigecycline
- Metronidazole plus cefazolin, cefuroxime, ceftriaxone, cefotaxime, levofloxacin, or ciprofloxacin
Important Notes
- Antibiotic treatment is most appropriate for uncomplicated cases without perforation, abscess, or appendicolith, and patients with severe symptoms, signs of perforation, or systemic illness should undergo immediate surgical evaluation rather than antibiotic therapy alone 1.
- Approximately 30% of patients treated with antibiotics alone may experience recurrence within a year, and the risk of recurrence should be discussed with patients when deciding on treatment options 1.
From the FDA Drug Label
In patients treated for IAI (primarily patients with perforated or complicated appendicitis), the clinical success rates were 83.7% (36/43) for ertapenem and 63. 6% (7/11) for ticarcillin/clavulanate in the EPP analysis.
The antibiotics used to treat acute appendicitis are:
- Ertapenem
- Ticarcillin/clavulanate
- Cefotetan
- Ceftriaxone 2
From the Research
Antibiotics Used to Treat Acute Appendicitis
- Broad-spectrum antibiotics, such as piperacillin-tazobactam monotherapy or combination therapy with either cephalosporins or fluoroquinolones with metronidazole, are used to treat uncomplicated acute appendicitis 3
- Amoxicillin + clavulanic acid, cefotaxime, or a fluoroquinolone, often with metronidazole or tinidazole, have been used in antibiotic therapy for acute appendicitis 4
- Oral moxifloxacin, IV ertapenem plus oral levofloxacin and metronidazole, and ciprofloxacin plus metronidazole have been studied as treatment options for uncomplicated acute appendicitis 5, 6
- Ceftriaxone plus metronidazole and anti-pseudomonal antibiotics, such as cefepime, piperacillin/tazobactam, ciprofloxacin, imipenem, or meropenem, have been compared for perforated appendicitis in children 7
Treatment Effectiveness
- Antibiotic therapy has been shown to be effective in treating uncomplicated acute appendicitis, with success rates ranging from 63% to 77% 3, 5, 6
- The choice of antibiotic regimen may influence treatment outcomes, with some studies suggesting that broader-spectrum regimens may not offer significant benefits over narrower-spectrum options 7
- Treatment with antibiotics rather than surgery is appropriate in selected patients with uncomplicated appendicitis, with considerations including patient preferences, risk of adverse outcomes, and CT findings 3