What is the treatment for diverticulitis?

Treatment for Diverticulitis

For uncomplicated diverticulitis, treatment should be based on patient risk factors, with immunocompetent patients without systemic manifestations receiving symptomatic treatment alone (clear liquid diet and oral analgesics), while high-risk patients require antibiotic therapy for 4-7 days. 1

Patient Classification and Treatment Approach

Uncomplicated Diverticulitis

• Low-risk patients (immunocompetent without systemic manifestations):

  • Symptomatic treatment only: clear liquid diet, oral analgesics
  • Re-evaluation within 7 days
  • No antibiotics required
  • Outpatient management appropriate 1

• High-risk patients (immunocompromised, elderly, with comorbidities, or systemic manifestations):

  • Antibiotic therapy for 4-7 days
  • Oral regimens if outpatient: amoxicillin-clavulanate or ciprofloxacin plus metronidazole
  • For penicillin-allergic patients: ciprofloxacin plus metronidazole 1
  • Immunocompromised patients require longer antibiotic courses (10-14 days) 1

Complicated Diverticulitis

• Small diverticular abscesses:

  • Antibiotic therapy alone for 7 days 1

• Large diverticular abscesses:

  • Percutaneous drainage combined with antibiotic therapy for 4 days
  • If drainage not feasible, antibiotics alone
  • Critically ill or immunocompromised patients require surgical intervention 1

• Peritonitis:

  • Inpatient management with IV antibiotics (gram-negative and anaerobic coverage)
  • Surgical intervention may be necessary 2
  • Laparoscopic peritoneal lavage and drainage may be considered in very selected patients with generalized peritonitis, but is not first-line treatment 2

Antibiotic Selection

Outpatient Regimens

• Amoxicillin-clavulanate
• Ciprofloxacin plus metronidazole 1

Inpatient Regimens

• IV antibiotics with gram-negative and anaerobic coverage
• Switch to oral when clinically improved 1

Outpatient vs. Inpatient Management

Outpatient management is appropriate for patients who:

• Are immunocompetent with uncomplicated diverticulitis
• Can tolerate oral intake
• Have no significant comorbidities
• Have adequate pain control with oral analgesics
• Have appropriate home support
• Have stable vital signs 1

Recent evidence shows that oral antibiotics are as effective as intravenous antibiotics for uncomplicated diverticulitis in the outpatient setting 3, which can reduce healthcare burden.

Prevention Strategies

To prevent recurrence of diverticulitis:

• High-fiber diet
• Regular physical activity
• Maintaining normal BMI
• Smoking cessation
• Avoiding non-aspirin NSAIDs 1

Important Considerations

• Patients with comorbidities, significant frailty, refractory symptoms, vomiting, elevated inflammatory markers, fluid collection, or longer segment of inflammation on CT require closer monitoring and possibly more aggressive treatment 1

• Risk factors for treatment failure include CT performed between midnight and 6 AM, Ambrosetti score of 4, and free air around the colon 4

• Routine colonoscopy is not required after an episode of uncomplicated diverticulitis, but should be considered for screening in individuals aged 50 years and older 2

• Patients with complicated diverticulitis have a significant risk of colorectal cancer and should undergo colonoscopy after resolution of the acute episode 2