Executive summary
- Most gastroenteritis is self-limiting, but dehydration risk is the key driver of harm.
- Assess dehydration systematically (intake, urine output, mental state, mucous membranes, cap refill, skin turgor) and recognise higher-risk groups (young infants, low birth weight, high stool/vomit frequency).
- Oral rehydration solution (ORS) is the main treatment: use small frequent volumes; continue breastfeeding and usual milk feeds.
- Avoid routine antiemetics/antidiarrhoeals in primary care; focus on fluids and safety-netting.
- Escalate early if shock, severe dehydration, altered consciousness, bilious vomiting, blood/mucus in stool with systemic features, or inability to keep fluids down.
Assessment (high-yield history)
- Duration and pattern: stool frequency/character, vomiting frequency, ability to tolerate fluids, and last wet nappy/urination.
- Exposure risks: contacts with similar illness, childcare outbreaks, travel, suspected foodborne exposure.
- Red flags for alternative diagnosis: non-blanching rash, neck stiffness, severe/localised abdominal pain, bilious vomit, significant lethargy/altered responsiveness.
- Higher dehydration risk: age <1 year (esp <6 months), low birth weight, >5 watery stools/24h, >2 vomits/24h, poor pre-presentation fluid intake.
Management (ORS and feeding plan)
- Continue breastfeeding and usual milk feeds; do not routinely dilute milk.
- ORS strategy: give small frequent sips (or spoon/ syringe) and persist even if vomiting occurs (pause briefly then restart slowly).
- After rehydration: encourage normal diet as tolerated; avoid sugary fizzy drinks/undiluted fruit juice during acute illness (can worsen diarrhoea).
- Ongoing losses: for children at increased risk, ORS “top ups” after large watery stools can reduce recurrence of dehydration (use local guidance for exact volumes).
- When IV/NG fluids are needed: severe dehydration, shock, persistent vomiting with inability to tolerate ORS, or clinical deterioration → hospital pathway.
Investigations and infection control
- Stool testing is not routine; consider if recent travel, symptoms persist beyond ~7 days, diagnostic uncertainty, immunocompromised, or blood/mucus in stool.
- Safeguarding household: hand hygiene, separate towels, disinfect high-touch surfaces; keep off nursery/school until symptom-free per local public health advice.
Frequently asked questions
Should I prescribe an antiemetic to help ORS stay down?
Not routinely in primary care. Most children can be rehydrated with small frequent ORS volumes and good guidance; escalate if vomiting prevents hydration or if dehydration is significant.
Do I stop feeding while rehydrating?
No. Continue breastfeeding and usual milk feeds. Once rehydrated, resume normal diet as tolerated.
When should I worry about meningitis or sepsis?
Non-blanching rash, altered consciousness, neck stiffness, bulging fontanelle, or systemic toxicity — urgent assessment.
How long should symptoms last?
Often vomiting settles within a few days and diarrhoea within 1–2 weeks, but ensure follow-up if persistent beyond expected course or if red flags emerge.
When do I send to hospital?
Shock/severe dehydration, persistent inability to keep fluids down, significant lethargy/altered responsiveness, bilious vomiting, severe abdominal pain, or clinician concern.
Transparency
This page is an educational, clinician-written summary of publicly available NICE guidance intended for trained healthcare professionals. It uses original wording (not copied text) and should be used alongside the full NICE source, local pathways, and clinical judgement. Doses provided are for general reference; always check the BNF/SPC.