What is the recommended dosage of Augmentin (amoxicillin/clavulanate) for diverticulitis?

Recommended Dosage of Augmentin for Diverticulitis

For complicated diverticulitis, the recommended dosage of Augmentin (amoxicillin-clavulanate) is 875 mg/125 mg every 12 hours or 500 mg/125 mg every 8 hours. 1

Classification of Diverticulitis and Need for Antibiotics

Diverticulitis is classified into two main categories:

1. Uncomplicated diverticulitis:

   • Current consensus suggests antibiotics are not necessary for immunocompetent patients with uncomplicated diverticulitis 2
   • Multiple studies have shown that withholding antibiotics does not affect recovery or complication rates in mild uncomplicated cases 2

2. Complicated diverticulitis (requires antibiotics):

   • Presence of abscess, phlegmon, fistula, obstruction, bleeding, or perforation 3
   • Patients with systemic symptoms (persistent fever, chills)
   • Increasing leukocytosis
   • Immunocompromised patients
   • Elderly patients (>80 years)
   • Patients with significant comorbidities 4

Antibiotic Regimens for Diverticulitis

Oral Therapy (for outpatient management or after improvement with IV therapy):

• Augmentin (amoxicillin-clavulanate):
  • 875 mg/125 mg every 12 hours OR
  • 500 mg/125 mg every 8 hours 1
  • Should be taken at the start of a meal to minimize gastrointestinal intolerance 1
  • Duration: Typically 7-10 days 3

Alternative Oral Regimens (for penicillin allergy):

• Ciprofloxacin plus metronidazole 3
• Cefalexin with metronidazole 3, 4

Intravenous Therapy (for patients unable to tolerate oral intake or with severe infection):

• Ceftriaxone plus metronidazole
• Piperacillin-tazobactam
• Ampicillin/sulbactam 3, 4

Treatment Approach Based on Severity

1. Uncomplicated diverticulitis:

   • Observation with pain management (typically acetaminophen)
   • Clear liquid diet
   • Antibiotics only if: systemic symptoms, increasing leukocytosis, age >80, pregnancy, immunocompromised status, or significant comorbidities 4

2. Complicated diverticulitis:

   • Intravenous antibiotics
   • Percutaneous drainage for abscesses ≥4-5 cm
   • Surgical intervention for peritonitis or hemodynamic instability 3

Evidence on Comparative Effectiveness

A nationwide cohort study comparing amoxicillin-clavulanate to metronidazole-with-fluoroquinolone found:

• No differences in admission risk, urgent surgery risk, or elective surgery risk
• Higher risk of Clostridioides difficile infection with metronidazole-with-fluoroquinolone in Medicare patients 5
• This suggests amoxicillin-clavulanate is an effective first-line option with potentially fewer adverse effects

Monitoring and Follow-up

• Reassess at 4-7 days to confirm symptom improvement 3
• Monitor for signs of treatment failure: persistent symptoms or worsening clinical condition
• Colonoscopy recommended 4-6 weeks after resolution of complicated diverticulitis to rule out malignancy 3

Common Pitfalls to Avoid

1. Dosing errors: Do not substitute two 250 mg/125 mg tablets for one 500 mg/125 mg tablet, as they contain the same amount of clavulanic acid 1

2. Inappropriate antibiotic use: Avoid routine use of antibiotics for all uncomplicated diverticulitis cases 3

3. Delayed escalation of care: Promptly recognize treatment failure and consider imaging, alternative antibiotics, or surgical consultation

4. Missing atypical presentations: Elderly patients often present atypically, with only 50% showing typical lower quadrant pain 3