What is the recommended treatment for a diverticulitis flare-up with symptoms of nausea, frequent bowel movements, and bloating?

Treatment Recommendation for Acute Diverticulitis Flare-Up

For Michelle's current diverticulitis flare-up with nausea, frequent bowel movements, and bloating, antibiotics are NOT automatically indicated unless she has specific high-risk features—she should be assessed for immunocompromised status, severe systemic symptoms, or laboratory/imaging findings that warrant antibiotic therapy. 1, 2

Initial Assessment and Risk Stratification

Before prescribing antibiotics, Michelle needs evaluation for the following high-risk criteria that would justify antibiotic use in uncomplicated diverticulitis:

High-risk features requiring antibiotics: 1, 2, 3

• Immunocompromised status (steroids, chemotherapy, organ transplant)
• Systemic inflammatory response (persistent fever >101°F, chills)
• Elevated white blood cell count (>15 × 10^9 cells/L)
• Elevated C-reactive protein (>140 mg/L)
• Symptoms lasting >5 days
• Persistent vomiting (not just nausea)
• Age >80 years
• Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes)
• ASA score III or IV

If Michelle has NONE of these features, the current evidence strongly supports observation without antibiotics, as antibiotics do not accelerate recovery, prevent complications, or reduce recurrence rates in immunocompetent patients with uncomplicated diverticulitis. 1, 2, 4

Recommended Management Based on Risk Profile

For Low-Risk Patients (No High-Risk Features):

Supportive care without antibiotics: 1, 2, 3

• Clear liquid diet during acute phase, advancing as symptoms improve
• Pain control with acetaminophen (avoid NSAIDs as they increase diverticulitis risk)
• Adequate hydration
• Bowel rest initially
• Re-evaluation within 7 days, or earlier if symptoms worsen

For High-Risk Patients (Any High-Risk Feature Present):

Oral antibiotic regimens (4-7 days for immunocompetent patients): 1, 2, 3

• First-line: Amoxicillin-clavulanate (dose per standard guidelines)
• Alternative: Ciprofloxacin 500 mg twice daily PLUS metronidazole 500 mg three times daily
• Alternative: Cefalexin plus metronidazole

Important: Avoid alcohol until at least 48 hours after completing metronidazole to prevent disulfiram-like reactions. 1

Outpatient vs. Inpatient Decision

Michelle can be managed as an outpatient if: 1, 2

• She can tolerate oral intake
• She has adequate home support
• No signs of complicated diverticulitis (abscess, perforation)
• No severe systemic symptoms or sepsis

Hospitalization is required if: 1, 2, 3

• Unable to tolerate oral intake
• Signs of peritonitis or severe systemic symptoms
• Suspected complicated diverticulitis
• Immunocompromised with severe presentation
• Inadequate social support for home management

Critical Pitfalls to Avoid

Do not automatically prescribe antibiotics based solely on history of previous episodes requiring antibiotics. The current guidelines have shifted away from routine antibiotic use in uncomplicated cases, and each episode should be assessed independently for high-risk features. 1, 2, 4

Do not assume all diverticulitis flares are the same. Michelle's current symptoms (nausea, frequent bowel movements, bloating) may represent uncomplicated disease that can be managed conservatively, whereas her previous hospitalization may have involved complicated disease or high-risk features. 1, 2

Do not delay imaging if there is diagnostic uncertainty. If Michelle has not had CT confirmation of diverticulitis in this episode, and especially if she has any high-risk features, CT imaging should be obtained to confirm uncomplicated vs. complicated disease. 1, 3

Follow-Up and Monitoring

Warning signs requiring immediate medical attention: 1, 2

• Fever >101°F
• Severe or worsening abdominal pain
• Persistent vomiting (not just nausea)
• Inability to tolerate oral intake
• Signs of dehydration
• No improvement within 2-3 days of treatment

Scheduled follow-up: Re-evaluation within 7 days, or sooner if clinical deterioration occurs. 1, 2

Long-Term Prevention Strategy

After resolution of the acute episode: 1

• High-quality diet (high fiber from fruits, vegetables, whole grains, legumes; low in red meat and sweets)
• Regular physical activity
• Achieve/maintain normal BMI
• Avoid smoking
• Avoid regular NSAID and opioid use when possible
• Do NOT restrict nuts, corn, popcorn, or seeds (this outdated advice is not evidence-based)