1 Guidance

The following guidance is based on the best available evidence. The full guideline gives details of the methods and the evidence used to develop the guidance.

For the purposes of this guideline, an 'infant' is defined as a child younger than 1 year. 'Remote assessment' refers to situations in which a child is assessed by a healthcare professional who is unable to examine the child because the child is geographically remote from the assessor (for example, telephone calls to NHS Direct).

1.1 Diagnosis

1.1.1 Clinical diagnosis

1.1.1.1 Suspect gastroenteritis if there is a sudden change in stool consistency to loose or watery stools, and/or a sudden onset of vomiting.

1.1.1.2 If you suspect gastroenteritis, ask about:

  • recent contact with someone with acute diarrhoea and/or vomiting and

  • exposure to a known source of enteric infection (possibly contaminated water or food) and

  • recent travel abroad.

1.1.1.3 Be aware that in children with gastroenteritis:

  • diarrhoea usually lasts for 5–7 days, and in most it stops within 2 weeks

  • vomiting usually lasts for 1–2 days, and in most it stops within 3 days.

1.1.1.4 Consider any of the following as possible indicators of diagnoses other than gastroenteritis:

  • fever:

    • temperature of 38°C or higher in children younger than 3 months

    • temperature of 39°C or higher in children aged 3 months or older

  • shortness of breath or tachypnoea

  • altered conscious state

  • neck stiffness

  • bulging fontanelle in infants

  • non-blanching rash

  • blood and/or mucus in stool

  • bilious (green) vomit

  • severe or localised abdominal pain

  • abdominal distension or rebound tenderness.

1.1.2 Laboratory investigations

1.1.2.1 Consider performing stool microbiological investigations if:

  • the child has recently been abroad or

  • the diarrhoea has not improved by day 7 or

  • there is uncertainty about the diagnosis of gastroenteritis.

1.1.2.2 Perform stool microbiological investigations if:

  • you suspect septicaemia or

  • there is blood and/or mucus in the stool or

  • the child is immunocompromised.

1.1.2.3 Notify and act on the advice of the public health authorities if you suspect an outbreak of gastroenteritis.

1.1.2.4 If stool microbiology is performed:

  • collect, store and transport stool specimens as advised by the investigating laboratory

  • provide the laboratory with relevant clinical information.

1.1.2.5 Perform a blood culture if giving antibiotic therapy.

1.1.2.6 In children with Escherichia coli O157:H7 infection, seek specialist advice on monitoring for haemolytic uraemic syndrome.

1.2 Assessing dehydration and shock

1.2.1 Clinical assessment

1.2.1.1 During remote or face-to-face assessment ask whether the child:

  • appears unwell

  • has altered responsiveness, for example is irritable or lethargic

  • has decreased urine output

  • has pale or mottled skin

  • has cold extremities.

1.2.1.2 Recognise that the following are at increased risk of dehydration:

  • children younger than 1 year, particularly those younger than 6 months

  • infants who were of low birth weight

  • children who have passed more than five diarrhoeal stools in the previous 24 hours

  • children who have vomited more than twice in the previous 24 hours

  • children who have not been offered or have not been able to tolerate supplementary fluids before presentation

  • infants who have stopped breastfeeding during the illness

  • children with signs of malnutrition.

1.2.1.3 Use table 1 to detect clinical dehydration and shock.

Table 1 Symptoms and signs of clinical dehydration and shock

Interpret symptoms and signs taking risk factors for dehydration into account (see 1.2.1.2). Within the category of 'clinical dehydration' there is a spectrum of severity indicated by increasingly numerous and more pronounced symptoms and signs. For clinical shock, one or more of the symptoms and/or signs listed would be expected to be present. Dashes (–) indicate that these clinical features do not specifically indicate shock. Symptoms and signs with red flags may help to identify children at increased risk of progression to shock. If in doubt, manage as if there are symptoms and/or signs with red flags.

Increasing severity of dehydration

No clinically detectable dehydration

Clinical dehydration

Clinical shock

Symptoms (remote and face-to-face assessments)

Appears well

Red flag Appears to be unwell or deteriorating

Alert and responsive

Red flag Altered responsiveness (for example, irritable, lethargic)

Decreased level of consciousness

Normal urine output

Decreased urine output

Skin colour unchanged

Skin colour unchanged

Pale or mottled skin

Warm extremities

Warm extremities

Cold extremities

Signs (face-to-face assessments)

Alert and responsive

Red flag Altered responsiveness (for example, irritable, lethargic)

Decreased level of consciousness

Skin colour unchanged

Skin colour unchanged

Pale or mottled skin

Warm extremities

Warm extremities

Cold extremities

Eyes not sunken

Red flag Sunken eyes

Moist mucous membranes (except after a drink)

Dry mucous membranes (except for 'mouth breather')

Normal heart rate

Red flag Tachycardia

Tachycardia

Normal breathing pattern

Red flag Tachypnoea

Tachypnoea

Normal peripheral pulses

Normal peripheral pulses

Weak peripheral pulses

Normal capillary refill time

Normal capillary refill time

Prolonged capillary refill time

Normal skin turgor

Red flag Reduced skin turgor

Normal blood pressure

Normal blood pressure

Hypotension (decompensated shock)

1.2.1.4 Suspect hypernatraemic dehydration if there are any of the following:

  • jittery movements

  • increased muscle tone

  • hyperreflexia

  • convulsions

  • drowsiness or coma.

1.2.2 Laboratory investigations for assessing dehydration

1.2.2.1 Do not routinely perform blood biochemical testing.

1.2.2.2 Measure plasma sodium, potassium, urea, creatinine and glucose concentrations if:

  • intravenous fluid therapy is required or

  • there are symptoms and/or signs that suggest hypernatraemia.

1.2.2.3 Measure venous blood acid–base status and chloride concentration if shock is suspected or confirmed.

1.3 Fluid management

1.3.1 Primary prevention of dehydration

1.3.1.1 In children with gastroenteritis but without clinical dehydration:

  • continue breastfeeding and other milk feeds

  • encourage fluid intake

  • discourage the drinking of fruit juices and carbonated drinks, especially in those at increased risk of dehydration (see 1.2.1.2)

  • offer ORS solution as supplemental fluid to those at increased risk of dehydration (see 1.2.1.2).

1.3.2 Treating dehydration

1.3.2.1 Use ORS solution to rehydrate children, including those with hypernatraemia, unless intravenous fluid therapy is indicated (see 1.3.3.1 and 1.3.3.5).

1.3.2.2 In children with clinical dehydration, including hypernatraemic dehydration:

  • use low-osmolarity ORS solution (240–250 mOsm/l)[5] for oral rehydration therapy

  • give 50 ml/kg for fluid deficit replacement over 4 hours as well as maintenance fluid

  • give the ORS solution frequently and in small amounts

  • consider supplementation with their usual fluids (including milk feeds or water, but not fruit juices or carbonated drinks) if they refuse to take sufficient quantities of ORS solution and do not have red flag symptoms or signs (see table 1)

  • consider giving the ORS solution via a nasogastric tube if they are unable to drink it or if they vomit persistently

  • monitor the response to oral rehydration therapy by regular clinical assessment.

1.3.3 Intravenous fluid therapy

1.3.3.1 Use intravenous fluid therapy for clinical dehydration if:

  • shock is suspected or confirmed

  • a child with red flag symptoms or signs (see table 1) shows clinical evidence of deterioration despite oral rehydration therapy

  • a child persistently vomits the ORS solution, given orally or via a nasogastric tube.

1.3.3.2 Treat suspected or confirmed shock with a rapid intravenous infusion of 20 ml/kg of 0.9% sodium chloride solution.

1.3.3.3 If a child remains shocked after the first rapid intravenous infusion:

  • immediately give another rapid intravenous infusion of 20 ml/kg of 0.9% sodium chloride solution and

  • consider possible causes of shock other than dehydration.

1.3.3.4 Consider consulting a paediatric intensive care specialist if a child remains shocked after the second rapid intravenous infusion.

1.3.3.5 When symptoms and/or signs of shock resolve after rapid intravenous infusions, start rehydration with intravenous fluid therapy (see 1.3.3.6).

1.3.3.6 If intravenous fluid therapy is required for rehydration (and the child is not hypernatraemic at presentation):

  • use an isotonic solution such as 0.9% sodium chloride, or 0.9% sodium chloride with 5% glucose, for fluid deficit replacement and maintenance

  • for those who required initial rapid intravenous fluid boluses for suspected or confirmed shock, add 100 ml/kg for fluid deficit replacement to maintenance fluid requirements, and monitor the clinical response

  • for those who were not shocked at presentation, add 50 ml/kg for fluid deficit replacement to maintenance fluid requirements, and monitor the clinical response

  • measure plasma sodium, potassium, urea, creatinine and glucose at the outset, monitor regularly, and alter the fluid composition or rate of administration if necessary

  • consider providing intravenous potassium supplementation once the plasma potassium level is known.

1.3.3.7 If intravenous fluid therapy is required in a child presenting with hypernatraemic dehydration:

1.3.3.8 obtain urgent expert advice on fluid management

1.3.3.9 use an isotonic solution such as 0.9% sodium chloride, or 0.9% sodium chloride with 5% glucose for fluid deficit replacement and maintenance

1.3.3.10 replace the fluid deficit slowly – typically over 48 hours

  • monitor the plasma sodium frequently, aiming to reduce it at a rate of less than 0.5 mmol/l per hour.

1.3.3.11 Attempt early and gradual introduction of oral rehydration therapy during intravenous fluid therapy. If tolerated, stop intravenous fluids and complete rehydration with oral rehydration therapy.

1.3.4 Fluid management after rehydration

1.3.4.1 After rehydration:

  • encourage breastfeeding and other milk feeds

  • encourage fluid intake

  • in children at increased risk of dehydration recurring, consider giving 5 ml/kg of ORS solution after each large watery stool. These include:

    • children younger than 1 year, particularly those younger than 6 months

    • infants who were of low birth weight

    • children who have passed more than five diarrhoeal stools in the previous 24 hours

    • children who have vomited more than twice in the previous 24 hours.

1.3.4.2 Restart oral rehydration therapy if dehydration recurs after rehydration.

1.4 Nutritional management

1.4.1.1 During rehydration therapy:

  • continue breastfeeding

  • do not give solid foods

  • in children with red flag symptoms or signs (see table 1), do not give oral fluids other than ORS solution

  • in children without red flag symptoms or signs (see table 1), do not routinely give oral fluids other than ORS solution; however, consider supplementation with the child's usual fluids (including milk feeds or water, but not fruit juices or carbonated drinks) if they consistently refuse ORS solution.

1.4.1.2 After rehydration:

  • give full-strength milk straight away

  • reintroduce the child's usual solid food

  • avoid giving fruit juices and carbonated drinks until the diarrhoea has stopped.

1.5 Antibiotic therapy

1.5.1.1 Do not routinely give antibiotics to children with gastroenteritis.

1.5.1.2 Give antibiotic treatment to all children:

  • with suspected or confirmed septicaemia

  • with extra-intestinal spread of bacterial infection

  • younger than 6 months with salmonella gastroenteritis

  • who are malnourished or immunocompromised with salmonella gastroenteritis

  • with Clostridium difficile-associated pseudomembranous enterocolitis, giardiasis, dysenteric shigellosis, dysenteric amoebiasis or cholera.

1.5.1.3 For children who have recently been abroad, seek specialist advice about antibiotic therapy.

1.6 Other therapies

1.6.1.1 Do not use antidiarrhoeal medications.

1.7 Escalation of care

1.7.1.1 During remote assessment:

  • arrange emergency transfer to secondary care for children with symptoms suggesting shock (see table 1)

  • refer for face-to-face assessment children:

    • with symptoms suggesting an alternative serious diagnosis (see 1.1.1.4) or

    • at high risk of dehydration, taking into account the risk factors listed in 1.2.1.2 or

    • with symptoms suggesting clinical dehydration (see table 1) or

    • whose social circumstances make remote assessment unreliable

  • provide a 'safety net' for children who do not require referral. The safety net should include information for parents and carers on how to:

    • recognise developing red flag symptoms (see table 1) and

    • get immediate help from an appropriate healthcare professional if red flag symptoms develop.

1.7.1.2 During face-to-face assessment:

  • arrange emergency transfer to secondary care for children with symptoms or signs suggesting shock (see table 1)

  • consider repeat face-to-face assessment or referral to secondary care for children:

    • with symptoms and/or signs suggesting an alternative serious diagnosis (see 1.1.1.4) or

    • with red flag symptoms and/or signs (see table 1) or

    • whose social circumstances require continued involvement of healthcare professionals

  • provide a safety net for children who will be managed at home. The safety net should include:

    • information for parents and carers on how to recognise developing red flag symptoms (see table 1) and

    • information on how to get immediate help from an appropriate healthcare professional if red flag symptoms develop and

    • arrangements for follow-up at a specified time and place, if necessary.

1.8 Information and advice for parents and carers

1.8.1 Caring for a child with diarrhoea and vomiting at home

1.8.1.1 Inform parents and carers that:

  • most children with gastroenteritis can be safely managed at home, with advice and support from a healthcare professional if necessary

  • the following symptoms may indicate dehydration:

    • appearing to get more unwell

    • changing responsiveness (for example, irritability, lethargy)

    • decreased urine output

    • pale or mottled skin

    • cold extremities

  • they should contact a healthcare professional if symptoms of dehydration develop.

1.8.1.2 Advise parents and carers of children:

  • who are not clinically dehydrated and are not at increased risk of dehydration (see 1.2.1.2):

    • to continue usual feeds, including breast or other milk feeds

    • to encourage the child to drink plenty of fluids

    • to discourage the drinking of fruit juices and carbonated drinks

  • who are not clinically dehydrated but who are at increased risk of dehydration (see 1.2.1.2):

    • to continue usual feeds, including breast or other milk feeds

    • to encourage the child to drink plenty of fluids

    • to discourage the drinking of fruit juices and carbonated drinks

    • to offer ORS solution as supplemental fluid

  • with clinical dehydration:

    • that rehydration is usually possible with ORS solution

    • to make up the ORS solution according to the instructions on the packaging

    • to give 50 ml/kg of ORS solution for rehydration plus maintenance volume over a 4-hour period

    • to give this amount of ORS solution in small amounts, frequently

    • to seek advice if the child refuses to drink the ORS solution or vomits persistently

    • to continue breastfeeding as well as giving the ORS solution

    • not to give other oral fluids unless advised

    • not to give solid foods.

1.8.1.3 Advise parents and carers that after rehydration:

  • the child should be encouraged to drink plenty of their usual fluids, including milk feeds if these were stopped

  • they should avoid giving the child fruit juices and carbonated drinks until the diarrhoea has stopped

  • they should reintroduce the child's usual diet

  • they should give 5 ml/kg ORS solution after each large watery stool if you consider that the child is at increased risk of dehydration (see 1.2.1.2).

1.8.1.4 Advise parents and carers that:

  • the usual duration of diarrhoea is 5–7 days and in most children it stops within 2 weeks

  • the usual duration of vomiting is 1 or 2 days and in most children it stops within 3 days

  • they should seek advice from a specified healthcare professional if the child's symptoms do not resolve within these timeframes.

1.8.2 Preventing primary spread of diarrhoea and vomiting

1.8.2.1 Advise parents, carers and children that[6]:

  • washing hands with soap (liquid if possible) in warm running water and careful drying are the most important factors in preventing the spread of gastroenteritis

  • hands should be washed after going to the toilet (children) or changing nappies (parents/carers) and before preparing, serving or eating food

  • towels used by infected children should not be shared

  • children should not attend any school or other childcare facility while they have diarrhoea or vomiting caused by gastroenteritis

  • children should not go back to their school or other childcare facility until at least 48 hours after the last episode of diarrhoea or vomiting

  • children should not swim in swimming pools for 2 weeks after the last episode of diarrhoea.



[5] The 'BNF for children' (BNFC) 2008 edition lists the following products with this composition: Dioralyte, Dioralyte Relief, Electrolade and Rapolyte.

[6] This recommendation is adapted from the following guidelines commissioned by the Department of Health:

Health Protection Agency (2006) Guidance on Infection Control In Schools and other Child Care Settings. London.

Working Group of the former PHLS Advisory Committee on Gastrointestinal Infections (2004) Preventing person-to-person spread following gastrointestinal infections: guidelines for public health physicians and environmental health officers. Communicable Disease and Public Health 7(4):362–384.

  • National Institute for Health and Care Excellence (NICE)