Diverticulitis medication

Medication management for patients with diverticulitis depends on the severity and systemic involvement of the disease.

For patients with uncomplicated acute diverticulitis who are systemically well, a no antibiotic prescribing strategy can be considered, with the use of simple analgesia such as paracetamol. Patients should be advised to avoid NSAIDs and opioid analgesics due to increased risk of diverticular perforation. They should be instructed to re-present if symptoms persist or worsen.

For patients who are systemically unwell but do not meet criteria for complicated diverticulitis, oral antibiotics are recommended. The first-choice oral antibiotic is co-amoxiclav 500/125 mg three times daily for 5 days. If penicillin allergy or co-amoxiclav is unsuitable, alternatives include cefalexin plus metronidazole or trimethoprim plus metronidazole for 5 days. Ciprofloxacin with metronidazole may be used only if switching from intravenous ciprofloxacin with specialist advice due to safety concerns.

For patients with complicated acute diverticulitis or diverticular abscess admitted to secondary care, intravenous antibiotics are indicated. First-choice intravenous antibiotics include co-amoxiclav or cefuroxime with metronidazole. Antibiotics should be reviewed within 48 hours or after imaging and stepped down to oral therapy when possible. In cases of abscess, antibiotic treatment may continue for up to 14 days.

Antibiotics are not recommended to prevent recurrent diverticulitis.

Additionally, patients should be advised on diet and lifestyle modifications, and simple analgesia should be used for symptom control. Avoidance of NSAIDs and opioids is advised due to risk of perforation.

Referral to secondary care or specialist colorectal surgery should be considered for complicated cases, immunosuppressed patients, or those with frequent or severe recurrences.

Summary of key antibiotic regimens:

• Oral co-amoxiclav 500/125 mg TDS for 5 days (first-line for uncomplicated, systemically unwell patients)
• Cefalexin 500 mg BD or TDS plus metronidazole 400 mg TDS for 5 days (penicillin allergy alternative)
• Trimethoprim 200 mg BD plus metronidazole 400 mg TDS for 5 days (alternative)
• Intravenous co-amoxiclav 1.2 g TDS or cefuroxime 750 mg TDS plus metronidazole for complicated cases

Analgesia: Paracetamol preferred; avoid NSAIDs and opioids if possible.