What is the oral antibiotic regimen used for conservative management of appendicitis, following intravenous (IV) ceftriaxone (Rocephin) therapy as an inpatient?

From the Guidelines

For conservative management of appendicitis after IV ceftriaxone treatment as an inpatient, the recommended oral antibiotic tail typically consists of a combination of metronidazole 500 mg three times daily plus either ciprofloxacin 500 mg twice daily or amoxicillin-clavulanate 875/125 mg twice daily, for a total length of 7–10 days 123. This regimen is based on the most recent guidelines for the diagnosis and treatment of acute appendicitis, which suggest that the empiric antibiotic regimens for non-critically ill patients with community-acquired intra-abdominal infections should include a combination of antibiotics that provide broad-spectrum coverage against both aerobic and anaerobic bacteria commonly found in appendicitis 1. The choice between ciprofloxacin and amoxicillin-clavulanate often depends on local resistance patterns and patient factors such as allergies.

• Metronidazole targets anaerobic bacteria in the gut,
• while ciprofloxacin or amoxicillin-clavulanate covers gram-negative and gram-positive aerobes. Patients should complete the full course even if symptoms improve quickly, and should be advised to seek immediate medical attention if they develop worsening abdominal pain, fever, or other signs of treatment failure that might indicate the need for surgical intervention. It is essential to note that the role of antibiotics in the resolution of uncomplicated appendicitis is still being researched, and future studies may provide more insight into the optimal treatment approach 1.

From the FDA Drug Label

The overall clinical success rates in the clinically evaluable patients are shown in Table 18 Table 18: Clinical Success Rates in Patients with Complicated Intra-Abdominal Infections StudyMoxifloxacin Hydrochloride n/N (%) Comparator n/N (%) 95% Confidence Intervala North America (overall) 146/183 (79.8%)153/196 (78.1%)(-7.4%, 9.3%) Abscess 40/57 (70.2%) 49/63 (77.8%)b NAc Non-abscess106/126 (84.1%)104/133 (78.2%)NA International (overall) 199/246 (80.9%)218/265 (82.3%)(-8.9%, 4. 2%) Abscess 73/93 (78.5%)86/99 (86.9%)NA Non-abscess 126/153 (82.4%)132/166 (79.5%)NA

The oral antibiotic tail used for conservative management of appendicitis, when IV ceftriaxone was used as an inpatient, is amoxicillin/clavulanic acid as per the study that compared moxifloxacin 400 mg once a day for 5 to 14 days to intravenous ceftriaxone plus intravenous metronidazole followed by oral amoxicillin/clavulanic acid in the treatment of patients with cIAI 2.

From the Research

Oral Antibiotic Tail for Conservative Management of Appendicitis

When IV ceftriaxone is used as an inpatient, the oral antibiotic tail used for conservative management of appendicitis can be based on the following evidence:

• A study from 2010 3 suggests that appendicitis can be treated with a third-generation cephalosporin and an imidazole derivative, with 2 days of intravenous treatment followed by 10 days of oral treatment.
• Another study from 2009 4 compared the efficacy and safety of sequential intravenous to oral moxifloxacin with that of intravenous ceftriaxone plus metronidazole, followed by oral amoxicillin/clavulanate, and found that sequential moxifloxacin was noninferior to the comparator regimen.
• A 2012 study 5 used intravenous piperacillin plus tazobactam, followed by 9 days of oral ciprofloxacin plus metronidazole, and found that 77% of patients recovered without the need for surgery.
• A 2009 study 6 used intravenous antibiotics for 2 days, followed by oral treatment for 7 days, and found that antibiotic treatment was effective in patients with acute appendicitis, but had a high recurrent rate.
• A 2014 review 7 found that antibiotic therapy was usually administered intravenously first, then orally, with a total duration of 8 to 15 days, and that the antibiotics used were amoxicillin + clavulanic acid, cefotaxime, or a fluoroquinolone, often with metronidazole or tinidazole added.

Possible Oral Antibiotic Options

Based on the evidence, possible oral antibiotic options for conservative management of appendicitis include:

• Amoxicillin/clavulanic acid
• Ciprofloxacin plus metronidazole
• Moxifloxacin
• Cefotaxime (although this is typically an intravenous antibiotic)