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Dehydration Assessment in Children Under 5

Tick symptoms and signs to grade dehydration in a child under 5 with diarrhoea or vomiting.

By Dr Amer Sheikh, GP Updated 17 October 2026 Clinical review pending

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Dehydration categories

CategoryAction (NICE CG84)
No detectable dehydrationUsual fluids, including milk; ORS if at risk
Clinical dehydrationORS 50 mL/kg over 4 hours plus maintenance, little and often
Red flagsSame-day paediatric assessment
Suspected shockImmediate hospital transfer for IV fluids

Discourage fruit juice and fizzy drinks. Reassess regularly.

Frequently asked questions

How much ORS should a dehydrated child have?

50 mL/kg over 4 hours, plus maintenance fluid, in small frequent amounts.

What are signs of shock in a child?

Pale or mottled skin, cold extremities, weak pulse, prolonged capillary refill and decreased consciousness.

Can children keep breastfeeding?

Yes. Continue breastfeeding and other milk feeds.

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References

  1. NICE. Diarrhoea and vomiting caused by gastroenteritis in under 5s. CG84. nice.org.uk/guidance/cg84

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