A clinician is defining chronic diarrhoea for a teaching session. Which definition is correct?

Answer: B. Three or more loose or watery stools per day for more than 4 weeks

Definition of chronic diarrhoea

Chronic diarrhoea is the passage of three or more loose or watery stools per day for more than 4 weeks.

Why the duration matters

• The 4-week threshold separates it from acute diarrhoea (under 14 days, usually infective and self-limiting).
• Chronic diarrhoea often reflects underlying pathology and requires a structured evaluation and cause-specific management.

The clinician's role

1. Identify the pathophysiological mechanism (osmotic, secretory, inflammatory, malabsorptive, functional).
2. Exclude serious disease (look for red flags).
3. Provide targeted therapy and supportive care.

Key message

Chronic diarrhoea is not itself a diagnosis - classification by mechanism guides management.