What are the recommended oral antibiotics for uncomplicated diverticulitis?

From the Guidelines

For uncomplicated diverticulitis, oral antibiotics are recommended for patients with comorbidities, refractory symptoms, vomiting, CRP >140 mg/L, or baseline white blood cell count > 15 × 109 cells per liter, and the preferred regimens include a combination of metronidazole and a fluoroquinolone, or monotherapy with amoxicillin-clavulanate, for 4-7 days. The choice of antibiotics should be based on the patient's individual risk factors and the severity of the disease. According to the AGA clinical practice update on medical management of colonic diverticulitis 1, patients who are immunocompromised or have evidence of systemic inflammation, abscess, perforation, or obstruction should be treated with antibiotics. The recommended oral antibiotics for uncomplicated diverticulitis include:

• Metronidazole 500 mg three times daily plus ciprofloxacin 500 mg twice daily
• Metronidazole 500 mg three times daily plus trimethoprim-sulfamethoxazole (TMP-SMX) 160/800 mg twice daily
• Amoxicillin-clavulanate 875/125 mg twice daily as monotherapy These regimens provide broad-spectrum coverage against gram-negative and anaerobic bacteria commonly found in the colon. It is essential to note that the duration of treatment may vary depending on the patient's general health status, immune status, severity of presentation, CT findings, and patient expectations, as stated in the study by Peery et al. 1. Recent evidence suggests that some very mild cases of uncomplicated diverticulitis may resolve without antibiotics, but most clinicians still recommend antimicrobial therapy to prevent complications, as mentioned in the AGA clinical practice update 1. Patients should seek immediate medical attention if symptoms worsen, including increased pain, persistent fever, inability to tolerate oral intake, or development of new symptoms.

From the Research

Oral Antibiotics for Uncomplicated Diverticulitis

• The recommended oral antibiotics for uncomplicated diverticulitis include:
  • Metronidazole and ciprofloxacin 2, 3, 4
  • Amoxicillin-clavulanic acid or ciprofloxacin plus metronidazole in patients with penicillin allergy 5
  • Amoxicillin plus clavulanic acid 6
• These antibiotics have been shown to be effective in resolving inflammation and preventing complications in patients with uncomplicated diverticulitis
• Outpatient treatment with oral antibiotics has been demonstrated to be safe and effective in several studies 3, 4, 5, with success rates ranging from 92% to 97%
• The duration of oral antibiotic treatment typically ranges from 7 to 10 days 3, 4, 5

Key Findings

• A study published in 2016 found that outpatient treatment with oral antibiotics (metronidazole and ciprofloxacin) was effective in 92% of patients with uncomplicated diverticulitis 3
• A 2012 study found that outpatient treatment with oral antibiotics (metronidazole and ciprofloxacin) was viable in almost 95% of patients with uncomplicated acute diverticulitis, with a success rate of 94% 4
• A 2010 study found that ambulatory treatment with oral antibiotics (amoxicillin-clavulanic acid or ciprofloxacin plus metronidazole) was safe and effective in 97% of patients with uncomplicated acute diverticulitis 5

Treatment Considerations

• Patients with uncomplicated diverticulitis who are able to tolerate oral intake and have adequate family support may be candidates for outpatient treatment with oral antibiotics 3, 4, 5
• Patients with severe comorbidity or those who are unable to tolerate oral intake may require hospital admission and intravenous antibiotic treatment 5