What is the dosage of Rocephin (ceftriaxone) for treating diverticulitis?

Ceftriaxone (Rocephin) Dosing for Diverticulitis

For complicated diverticulitis requiring antibiotics, ceftriaxone should be dosed at 2 grams IV once daily in combination with metronidazole, with treatment duration of 4-7 days depending on patient factors and source control adequacy. 1

Treatment Algorithm Based on Clinical Severity

Uncomplicated Diverticulitis

• Conservative management without antibiotics is appropriate for immunocompetent patients with CT-confirmed uncomplicated acute diverticulitis 1
• Antibiotic therapy for ≤7 days should be reserved for immunocompromised or elderly patients with uncomplicated disease 1

Complicated Diverticulitis (Abscess or Perforation)

Standard Dosing Regimen:

• Ceftriaxone 2 grams IV once daily combined with metronidazole 1, 2
• This regimen has demonstrated non-inferiority to piperacillin/tazobactam for complicated diverticulitis, with comparable 30-day readmission rates (21.4% vs 15.9%) and no difference in antibiotic failure rates 2

Duration of Therapy:

• 4 days for immunocompetent, non-critically ill patients with adequate source control 1
• Up to 7 days for immunocompromised or critically ill patients, adjusted based on clinical response and inflammatory markers 1
• Patients with ongoing signs of infection beyond 7 days require diagnostic re-evaluation 1

Septic Shock from Diverticulitis

• Escalate to carbapenem therapy (meropenem 1g q6h by extended infusion, doripenem 500mg q8h by extended infusion, or imipenem/cilastatin 500mg q6h) rather than continuing ceftriaxone 1

Source Control Considerations

Small Diverticular Abscesses:

• Antibiotic therapy alone for 7 days is appropriate 1

Large Diverticular Abscesses:

• Percutaneous drainage combined with antibiotics for 4 days 1
• If drainage is not feasible in critically ill or immunocompromised patients, surgical intervention should be considered 1

Important Safety Considerations

Biliary Pseudolithiasis Risk:

• Ceftriaxone can cause reversible gallbladder sludge and stone formation, particularly with doses of 2g/day for ≥6 days 3, 4
• This adverse effect is typically asymptomatic and resolves within 6 days of discontinuation 3
• However, rare cases of acute necrotizing cholecystitis have occurred in elderly patients, especially with dehydration, fasting, or prolonged bed rest 4
• Monitor for right upper quadrant pain during and after therapy 4

High-Risk Patients:

• Patients who received oral antibiotics in the 7 days prior to admission have increased risk of treatment failure and readmission 2
• Consider this history when determining treatment intensity and monitoring frequency 2

Clinical Monitoring

Monitor the following to guide treatment duration:

• White blood cell count and left shift (>75%) 1
• C-reactive protein 1
• Procalcitonin 1
• Clinical signs: abdominal pain localization, fever, peritoneal signs 1