About this symptom
Diarrhoea refers to frequent loose or watery stools. Short episodes may follow infections, but symptoms that persist or return can be associated with medicines, food-related issues, impaired absorption or inflammatory bowel disease.
How the symptom or condition presents
Record how long diarrhoea has lasted, stool frequency, any blood or mucus, night-time symptoms, fever, weight changes, travel and recent medicines, particularly antibiotics. Blood in stool, nocturnal diarrhoea or unintentional weight loss warrant timely assessment.
Important differences and warning signs
The clinician selects tests based on the history. Depending on the situation these may include blood tests, stool testing for infections or inflammation, coeliac disease assessment or endoscopy. A vague test for dysbiosis does not substitute for identifying the actual cause.
Evaluation and individual care
Replace lost fluids and electrolytes as appropriate, but avoid taking antibiotics without evaluation. Antidiarrhoeal medicines may be unsuitable in the presence of fever or blood. Prolonged restrictive diets without a diagnosis can worsen nutrition.
Related information: Chronic constipation; Upper abdominal pain.
Signs and symptoms
- Repeated loose or watery stools and urgent bowel movements.
- Abdominal cramps, bloating, tiredness or mucus.
- Concerning features: blood, night-time diarrhoea, fever or weight loss.
Diagnosis and tests
Assessment considers duration, exposures, travel, medicines and alarm features. Blood and stool tests, coeliac disease testing and colonoscopy may be used when clinically indicated, rather than a generic microbiome panel.
Care and treatment approaches
Treatment targets the underlying cause and may include oral rehydration and electrolyte replacement. Antibiotics and antimotility drugs must not be used indiscriminately when fever or bleeding is present. Avoid prolonged exclusion diets without advice.
When to seek urgent care
Call 103 or 112 for fainting, severe dehydration, large amounts of blood in stool, extreme weakness or sudden severe abdominal pain. High fever with deterioration also calls for urgent assessment.
Frequently asked questions
Can stress cause diarrhoea?
Stress can affect bowel function, but it should not be assumed to explain persistent diarrhoea, especially with bleeding, night symptoms or weight loss.
Which tests might be needed?
Blood and stool tests are selected according to duration and risk factors; other investigations may be considered if alarm symptoms are present.
Are antibiotics useful for every case of diarrhoea?
No. Diarrhoea has many causes, and unnecessary antibiotics can cause harm. Treatment should follow assessment of the likely cause.
Information sources
Medical source links used when preparing this article.
Important information
A medical consultation is needed for diagnosis and treatment recommendations.
Self-treatment can be harmful to your health.
