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Diarrhoea is a sign of malabsorption of fluids and nutrients in the small or large intestine, most commonly an infection triggers this through inflammation and cellular invasion or destruction.

It can be viral, bacterial or parasitic, and though poo testing may help, it is often easy to tell the story. Persistent runny stools need further analysis to exclude more chronic or worrying causes in children like inflammatory bowel disease, cystic fibrosis or liver/pancreatic dysfunction. The simple principles of management in acute gastroenteritis are: protect the bum; let the stool flow, so you know what needs to be replaced and replace it with a solution designed to replace the fluid/glucose/sodium/potassium/bicarbonate lost in diarrhoea. If vomiting prevents this, then SAFE anti-nausea meds (e.g. Zofer/Zofran) can be used, or intravenous fluid may be necessary.

Useful signs of dehydration are:

  • The fontanelle level in <1 years
  • Tears?
  • Mucous membrane “wetness”
  • Sunken eyes
  • Energy levels (lying down is never good)
Diarrhoea Condition