Diverticulitis
Also known as Diverticular disease
This article is general health information for the selected condition. It is not a diagnosis and does not replace clinical judgement. If you have questions or need treatment advice, please consult a qualified healthcare professional.
What is diverticulitis?
Small pouches called diverticula commonly form in the colon wall with age. Having them is diverticulosis and usually causes no symptoms. Diverticulitis is what happens when one becomes inflamed or infected, typically causing pain in the left lower abdomen with fever. Most uncomplicated episodes settle without surgery.
Causes
- Increased pressure in the colon wall forming pouches
- Obstruction and inflammation of a diverticulum
- Low dietary fibre over many years
- Alterations in the gut microbiome
Symptoms
- Pain in the lower left abdomen, often persistent
- Fever
- Change in bowel habit
- Nausea and vomiting
- Bloating
- Rectal bleeding in some cases
Risk factors
- Age over 50
- Low fibre diet
- Obesity and physical inactivity
- Smoking
- Regular nonsteroidal anti inflammatory drug use
Diagnosis
- Clinical assessment of abdominal tenderness
- Blood tests showing raised inflammatory markers
- CT scan of the abdomen, the investigation of choice in acute disease
- Colonoscopy after recovery to exclude other pathology
Treatment
- Clear fluids and gradual reintroduction of diet in mild attacks
- Antibiotics for selected or complicated cases
- Analgesia avoiding nonsteroidal anti inflammatory drugs where possible
- Hospital admission for severe pain, sepsis or inability to eat
- Drainage of an abscess if one forms
- Surgery for perforation, obstruction or recurrent severe disease
- High fibre diet once recovered to reduce recurrence
Self care
- Follow clear fluids then reintroduce food gradually during an attack
- Complete any prescribed antibiotics
- Use paracetamol rather than anti inflammatory painkillers
- Return to a high fibre diet once recovered to reduce recurrence
- Increase fibre slowly to avoid bloating
- Stay well hydrated and physically active
When to see a doctor
Book an appointment if:
- Pain not settling after a few days
- Repeated episodes
- Persistent change in bowel habit after recovery
- Rectal bleeding
- To arrange the follow up colonoscopy after an attack
- Ongoing bloating or discomfort between episodes
Some symptoms need emergency care rather than an appointment. See the warning signs listed above.
Prevention
- Eat a high fibre diet with plenty of fluid
- Stay physically active and keep to a healthy weight
- Stop smoking
- Limit regular anti inflammatory painkiller use
- Nuts, seeds and popcorn do not need to be avoided
Outlook
Most uncomplicated attacks settle within a week and many people never have another. Around a fifth experience recurrence. Complicated disease with abscess, perforation or fistula needs drainage or surgery and is less predictable. A high fibre diet after recovery reduces the chance of further attacks.
Common questions
Do I need to avoid nuts and seeds?
This long standing advice has not been supported by research. Large studies found no increase in diverticulitis among people eating nuts, seeds or popcorn, and a high fibre diet is now encouraged.
Are antibiotics always needed?
Not always. Selected people with mild uncomplicated diverticulitis and no significant illness can be managed with observation and supportive care, though antibiotics remain standard for complicated or severe disease.
Why is a colonoscopy done afterwards?
Colon cancer can mimic diverticulitis on imaging. A colonoscopy several weeks after recovery confirms the diagnosis and excludes a tumour in the same area.
References
Important: Dard AI is not a medical device and does not diagnose, treat, or replace clinician judgement. This article is general information only. Always consult a qualified healthcare professional about diagnosis and treatment, and seek emergency care for severe or rapidly worsening symptoms.