Diarrhoea, Vomiting & Dehydration
Assess fluid losses, recognise alternative diagnoses and plan safe rehydration.
Quick revision ↓ Medical Dictionary
01Assess the whole child
Ask about stool and vomit pattern, intake, urine output, exposures and duration. Examine hydration, perfusion and mental state. Green bilious vomiting, severe localised pain or distension suggests a possible surgical problem and must not be assumed to be routine gastroenteritis.
02Recognise dehydration
Assess mucous membranes, eyes, activity, urine output and circulation in context. No single sign perfectly measures the deficit. Shock requires urgent treatment and reassessment; ongoing losses and comorbidity affect the plan, and severe malnutrition requires its own fluid pathway.
03Oral rehydration
Use appropriate oral rehydration solution for suitable children, giving small frequent amounts and continuing breastfeeding. Plain water, fizzy drinks and juice are not equivalent replacements for balanced rehydration solution. If oral intake fails or severity increases, reassess the route and level of care.
04Investigations and treatment
Most uncomplicated gastroenteritis does not need routine antibiotics or extensive testing. Bloody diarrhoea, prolonged symptoms, travel, immunocompromise or concern for an outbreak can change investigation and treatment. Avoid uncritical antimotility medicine use in children and follow local guidance for selected adjuncts.
05Recovery and prevention
Resume appropriate feeding as rehydration progresses and explain hygiene and infection-control advice. Provide return precautions for worsening lethargy, poor urine, persistent vomiting or blood in stools. Review a child whose course no longer fits uncomplicated gastroenteritis rather than extending the original label indefinitely.
High-Yield Revision
- Bilious vomiting is a warning sign.
- ORS differs from juice or plain water.
- Reassess ongoing losses and clinical response.
Common Pitfalls
- Diagnosing gastroenteritis despite a surgical presentation.
- Using a single sign to quantify every fluid deficit.
References & Further Reading
Read the relevant guideline sections alongside these original clinical teaching cases. Local pathways, available services and individual patient factors determine care.
Reference review: 28 September 2026. Consult current local protocols for prescribing, procedures and escalation.