From the Guidelines
For the treatment of acute appendicitis, the recommended antibiotics include amoxicillin-clavulanate, ceftriaxone plus metronidazole, or ciprofloxacin plus metronidazole, with a total treatment duration of 7-10 days for uncomplicated cases and 7-14 days for complicated cases 1. The choice of antibiotic regimen should be based on local microbiologic data, patient allergies, and formulary availability.
- For uncomplicated appendicitis, a regimen of intravenous antibiotics such as ceftriaxone (1-2g daily) plus metronidazole (500mg every 8 hours) can be used for 24-48 hours, followed by oral antibiotics like amoxicillin-clavulanate (875/125mg twice daily) or ciprofloxacin (500mg twice daily) plus metronidazole (500mg three times daily) to complete a 7-10 day course.
- For complicated appendicitis (perforation, abscess), a longer course of 7-14 days is recommended. It is essential to note that the use of broad-spectrum antibiotics like ertapenem and tigecycline should be reserved for cases with suspected or proven resistance to other antibiotics, due to concerns about the development of carbapenem-resistant Enterobacteriaceae and other resistant organisms 1. The results of recent studies, such as the APPAC II and APPAC III trials, may provide further guidance on the optimal antibiotic regimen for acute appendicitis, but until then, the current recommendations should be followed 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 recommended antibiotics for acute appendicitis include ertapenem and ticarcillin/clavulanate.
- Ertapenem has a clinical success rate of 83.7% in patients with complicated intra-abdominal infections (IAI), primarily those with perforated or complicated appendicitis 2.
- Ticarcillin/clavulanate has a clinical success rate of 63.6% in patients with IAI, primarily those with perforated or complicated appendicitis 2.
From the Research
Recommended Antibiotics for Acute Appendicitis
The following antibiotics have been recommended for the treatment of acute appendicitis:
- Amoxicillin + clavulanic acid 3
- Cefotaxime 3, 4
- Fluoroquinolones (e.g. ciprofloxacin, levofloxacin) 3, 5, 6
- Metronidazole 3, 5, 7, 6
- Piperacillin-tazobactam 5, 7, 4
- Moxifloxacin 6
- Ertapenem 6
Treatment Duration and Route of Administration
The duration of antibiotic treatment for acute appendicitis typically ranges from 7 to 15 days 3, 6. The route of administration may be intravenous initially, followed by oral antibiotics 3, 6.
Specific Treatment Regimens
Some studies have compared the effectiveness of different antibiotic regimens for acute appendicitis, including:
- Oral moxifloxacin vs intravenous ertapenem followed by oral levofloxacin and metronidazole 6
- Piperacillin-tazobactam vs cefotaxime, metronidazole, and gentamicin 4
Patient Selection for Antibiotic Therapy
The decision to use antibiotic therapy for acute appendicitis should be based on patient selection, including factors such as: