Treatment algorithm

Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups: see disclaimer

ACUTE

no dehydration

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1st line – 

fluid compensation/maintenance with oral rehydration therapy

Amount of oral rehydration solution (ORS) per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Small amounts of ORS should be given at frequent intervals and the volume gradually increased until the child can drink as desired.[43] Using a spoon or dropper for very small infants can significantly increase retention of ORS.

In a child who refuses to drink, squirting the ORS into the mouth with a syringe may help. Flavoured ORS or ORS popsicles, which may be more acceptable to some children, may also be tried.[62]

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Plus – 

age-appropriate diet

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

Back
Consider – 

ondansetron

Additional treatment recommended for SOME patients in selected patient group

Use of ondansetron should be considered when vomiting interferes with oral rehydration therapy.

Oral and single-dose ondansetron, rather than intravenous ondansetron, should be used if possible. In one randomised controlled trial (n = 194), one dose of oral ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5% (95% CI 0.20 to 0.72), and also showed a decrease in the number of vomiting episodes within 4 hours (incidence rate ratio 0.51 [95% CI 0.29 to 0.88]).[56] Usually 1 single dose (either oral or intravenous) is sufficient. Occasionally, patients may require a repeated dose. The medication can be used for both inpatients and outpatients, but only after the patient has been clinically assessed. The medication should be used with caution in children whose diarrhoea is a major concern, as the use of medication might aggravate the diarrhoea. Clinicians must balance the confirmed benefits of antiemetic therapy against the cost and risk of adverse events in patients with gastroenteritis-related vomiting.[57][58][59][60] [ Cochrane Clinical Answers logo ]

Primary options

ondansetron: children 8-15 kg: 2 mg orally as a single dose; children 16-30 kg: 4 mg orally as a single dose; children >30 kg: 8 mg orally as a single dose; children: 0.1 to 0.15 mg/kg intravenously as a single dose, maximum 4 mg

mild dehydration (<5%)

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1st line – 

rehydration with 50 mL/kg oral rehydration therapy over 4 hours

Signs of mild dehydration include: alert state; slightly decreased urine output; slightly increased thirst; slightly dry mucous membrane; slightly elevated heart rate; normal capillary refill; normal skin turgor; normal eyes; and normal anterior fontanelle.[40] Children with mild dehydration should be rehydrated with an oral rehydration solution (ORS) at 50 mL/kg over 4 hours.[40][42]

Small amounts of ORS should be given at frequent intervals and the volume gradually increased until the child can drink as desired.[43] Using a spoon or dropper for very small infants can significantly increase retention of ORS.

In a child who refuses to drink, squirting the ORS into the mouth with a syringe may help. Flavoured ORS or ORS popsicles, which may be more acceptable to some children, may also be tried.[62]

Back
Plus – 

fluid compensation/maintenance with oral rehydration therapy

Treatment recommended for ALL patients in selected patient group

Amount of oral rehydration solution (ORS) per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Small amounts of ORS should be given at frequent intervals and the volume gradually increased until the child can drink as desired.[43] Using a spoon or dropper for very small infants can significantly increase retention of ORS.

In a child who refuses to drink, squirting the ORS into the mouth with a syringe may help. Flavoured ORS or ORS popsicles, which may be more acceptable to some children, may also be tried.[62]

Back
Plus – 

age-appropriate diet

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

Back
Consider – 

ondansetron

Additional treatment recommended for SOME patients in selected patient group

Use of ondansetron should be considered when vomiting interferes with oral rehydration therapy.

Oral and single-dose ondansetron, rather than intravenous ondansetron, should be used if possible. In one randomised controlled trial (n = 194), one dose of oral ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5% (95% CI 0.20 to 0.72), and also showed a decrease in the number of vomiting episodes within 4 hours (incidence rate ratio 0.51 [95% CI 0.29 to 0.88]).[56] Usually 1 single dose (either oral or intravenous) is sufficient. Occasionally, patients may require a repeated dose. The medication can be used for both inpatients and outpatients, but only after the patient has been clinically assessed. The medication should be used with caution in children whose diarrhoea is a major concern, as the use of medication might aggravate the diarrhoea. Clinicians must balance the confirmed benefits of antiemetic therapy against the cost and risk of adverse events in patients with gastroenteritis-related vomiting.[57][58][59][60] [ Cochrane Clinical Answers logo ]

Primary options

ondansetron: children 8-15 kg: 2 mg orally as a single dose; children 16-30 kg: 4 mg orally as a single dose; children >30 kg: 8 mg orally as a single dose; children: 0.1 to 0.15 mg/kg intravenously as a single dose, maximum 4 mg

moderate dehydration (5% to 10%)

Back
1st line – 

rehydration with 100 mL/kg oral rehydration therapy over 4 hours

Signs of moderate dehydration include: alert state, fatigued, or irritable; decreased urine output; moderately increased thirst; dry mucous membranes; elevated heart rate; prolonged capillary refill; decreased skin turgor; sunken eyes; and sunken anterior fontanelle.[40] Children with moderate dehydration should be rehydrated with an oral rehydration solution (ORS) at 100 mL/kg over 4 hours.[40][42]

Small amounts of ORS should be given at frequent intervals and the volume gradually increased until the child can drink as desired.[43] Using a spoon or dropper for very small infants can significantly increase retention of ORS.

In a child who refuses to drink, squirting the ORS into the mouth with a syringe may help. Flavoured ORS or ORS popsicles, which may be more acceptable to some children, may also be tried.[62]

Back
Plus – 

fluid compensation/maintenance with oral rehydration therapy

Treatment recommended for ALL patients in selected patient group

Amount of oral rehydration solution per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Back
Plus – 

age-appropriate diet

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

Back
Consider – 

ondansetron

Additional treatment recommended for SOME patients in selected patient group

Use of ondansetron should be considered when vomiting interferes with oral rehydration therapy.

Oral and single-dose ondansetron, rather than intravenous ondansetron, should be used if possible. In one randomised controlled trial (n = 194), one dose of oral ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5% (95% CI 0.20 to 0.72), and also showed a decrease in the number of vomiting episodes within 4 hours (incidence rate ratio 0.51 [95% CI 0.29 to 0.88]).[56] Usually 1 single dose (either oral or intravenous) is sufficient. Occasionally, patients may require a repeated dose. The medication can be used for both inpatients and outpatients, but only after the patient has been clinically assessed. The medication should be used with caution in children whose diarrhoea is a major concern, as the use of medication might aggravate the diarrhoea. Clinicians must balance the confirmed benefits of antiemetic therapy against the cost and risk of adverse events in patients with gastroenteritis-related vomiting.[57][58][59][60] [ Cochrane Clinical Answers logo ]

Primary options

ondansetron: children 8-15 kg: 2 mg orally as a single dose; children 16-30 kg: 4 mg orally as a single dose; children >30 kg: 8 mg orally as a single dose; children: 0.1 to 0.15 mg/kg intravenously as a single dose, maximum 4 mg

Back
1st line – 

rehydration with 100 mL/kg nasogastric (NG) oral rehydration therapy over 4 hours

Signs of moderate dehydration include: alert state, fatigued, or irritable; decreased urine output; moderately increased thirst; dry mucous membranes; elevated heart rate; prolonged capillary refill; decreased skin turgor; sunken eyes; and sunken anterior fontanelle.[40]

Various measures may be attempted before proceeding to NG oral rehydration therapy:

Small amounts of oral rehydration solution (ORS) should be given at frequent intervals and the volume gradually increased until the child can drink as desired.[43]

Using a spoon or dropper for very small infants can significantly increase retention of ORS. In a child who refuses to drink, squirting the ORS into the mouth with a syringe may help.

Flavoured ORS or ORS ice-lollies, which may be more acceptable to some children, may also be tried.[62]

Children with moderate dehydration refusing to drink should be rehydrated with an ORS at 100 mL/kg over 4 hours through NG gavage.[40][42]

NG gavage should be considered before intravenous hydration is attempted.

Complications associated with NG gavage include trauma to the nose, oesophagus, and stomach, as well as aspiration.

Back
Plus – 

fluid compensation/maintenance with nasogastric (NG) oral rehydration therapy

Treatment recommended for ALL patients in selected patient group

Amount of NG oral rehydration solution per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Both ongoing losses and maintenance fluids are calculated together and given evenly through NG gavage over 24 hours.

Back
Plus – 

age-appropriate diet

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

Back
Consider – 

ondansetron

Additional treatment recommended for SOME patients in selected patient group

Use of ondansetron should be considered when vomiting interferes with oral rehydration therapy.

Oral and single-dose ondansetron, rather than intravenous ondansetron, should be used if possible. In one randomised controlled trial (n = 194), one dose of oral ondansetron decreased the proportion of children who continued vomiting within 4 hours from 42.9% to 19.5% (95% CI 0.20 to 0.72), and also showed a decrease in the number of vomiting episodes within 4 hours (incidence rate ratio 0.51 [95% CI 0.29 to 0.88]).[56] Usually 1 single dose (either oral or intravenous) is sufficient. Occasionally, patients may require a repeated dose. The medication can be used for both inpatients and outpatients, but only after the patient has been clinically assessed. The medication should be used with caution in children whose diarrhoea is a major concern, as the use of medication might aggravate the diarrhoea. Clinicians must balance the confirmed benefits of antiemetic therapy against the cost and risk of adverse events in patients with gastroenteritis-related vomiting.[57][58][59][60] [ Cochrane Clinical Answers logo ]

Primary options

ondansetron: children 8-15 kg: 2 mg orally as a single dose; children 16-30 kg: 4 mg orally as a single dose; children >30 kg: 8 mg orally as a single dose; children: 0.1 to 0.15 mg/kg intravenously as a single dose, maximum 4 mg

Back
Consider – 

intravenous fluids

Additional treatment recommended for SOME patients in selected patient group

Intravenous fluids may be considered for those patients refusing nasogastric (NG) gavage or for whom NG gavage may be contraindicated (choanal atresia, oesophageal atresia).

Complications of intravenous therapy include interstitial infiltration of fluid at the cannula site, pain, bleeding, phlebitis, and seizures.

Back
1st line – 

rehydration with intravenous fluids

Signs of moderate dehydration include: alert state, fatigued, or irritable; decreased urine output; moderately increased thirst; dry mucous membranes; elevated heart rate; prolonged capillary refill; decreased skin turgor; sunken eyes; and sunken anterior fontanelle.[40]

Contraindications to the use of oral rehydration therapy in this group include protracted vomiting, impaired consciousness, paralytic ileus, and monosaccharide malabsorption.[42]

Intravenous fluids should be given to replace the calculated deficit, ongoing losses, and the daily fluid maintenance requirement.

For children with mild and moderate dehydration, the deficit should be replenished in 4 hours and the rest given evenly throughout 24 hours. In these cases sodium chloride 0.45% with 5% glucose is the recommended intravenous fluid.

Early re-feeding should be started as soon as the physical condition of the patient allows.

Complications of intravenous therapy include interstitial infiltration of fluid at the cannula site, pain, bleeding, phlebitis, and seizures.

Back
Plus – 

fluid compensation/maintenance with intravenous fluids

Treatment recommended for ALL patients in selected patient group

Amount of intravenous fluids per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

For children with moderate dehydration sodium chloride 0.45% with 5% glucose is recommended to replace ongoing losses and maintain daily fluid requirements. This may be given evenly throughout 24 hours.

Back
Plus – 

age-appropriate diet

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

severe dehydration (>10%)

Back
1st line – 

rehydration with 20 mL/kg intravenous fluid over 1 hour

Signs of severe dehydration include: apathetic or lethargic state; markedly decreased or absent urine output; greatly increased thirst; very dry mucous membranes; greatly elevated heart rate; prolonged or minimal capillary refill; decreased skin turgor; very sunken eyes; very sunken anterior fontanelle; cold extremities; hypotension; and coma.[40]

Intravenous sodium chloride 0.9% or Ringer's lactate, 20 mL/kg, should be given over 1 hour.[40]

Vital signs should be monitored and the patient re-assessed on a regular basis.

Boluses of intravenous fluid may be required until pulse, perfusion, and mental status return to normal.[42]

Hypotonic saline solutions are inappropriate for intravenous rehydration.

Oral rehydration therapy should be started as soon as the patient is well enough to take it.

Complications of intravenous therapy include interstitial infiltration of fluid at the cannula site, pain, bleeding, phlebitis, and seizures.

Rehydration and maintenance of hydration should be continued until the vomiting and diarrhoea have subsided.

Back
Plus – 

post-stabilisation oral or nasogastric (NG) oral rehydration therapy maintenance

Treatment recommended for ALL patients in selected patient group

Oral rehydration therapy should be started as soon as the patient is well enough to take it.

Amount of oral rehydration solution per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Both ongoing losses and maintenance fluids are calculated together and given evenly through NG gavage over 24 hours.

Back
Plus – 

age-appropriate diet once stable

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as tolerated.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout, even during the initial rehydration phases, if possible.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

Back
Plus – 

fluid compensation/maintenance with intravenous fluids

Treatment recommended for ALL patients in selected patient group

Contraindications to the use of oral rehydration therapy in this group include protracted vomiting, impaired consciousness, paralytic ileus, and monosaccharide malabsorption.[42]

Once rehydrated, sodium chloride 0.45% with 5% glucose is recommended to replace ongoing losses and maintain daily fluid requirements.

Amount of intravenous fluids per episode of vomiting or diarrhoeal stool: weight <10 kg = 60 to 120 mL, weight >10 kg = 120 to 240 mL.[42] This should be continued until the vomiting and diarrhoea have subsided.

Daily fluid maintenance requirement is 100 mL/kg for the first 10 kg body weight, 50 mL/kg for the next 10 kg, and 20 mL/kg for each subsequent 1 kg over 20 kg.

Both ongoing losses and maintenance fluids are calculated together and given evenly over 24 hours.

Early re-feeding should be started as soon as the physical condition of the patient allows.

Complications of intravenous therapy include interstitial infiltration of fluid at the cannula site, pain, bleeding, phlebitis, and seizures.

Back
Plus – 

age-appropriate diet once stable

Treatment recommended for ALL patients in selected patient group

Children should continue to be fed an age-appropriate diet as soon as the physical condition allows.[40][42]

For infants who are breastfed, breastfeeding should be continued throughout, even during the initial rehydration phases, if possible.[40][42]

It is not necessary to dilute formula or to give lactose-free formula in re-feeding non-breastfed infants.[40][42]

Infants should be offered more frequent bottle or breastfeedings.

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Please note that formulations/routes and doses may differ between drug names and brands, drug formularies, or locations. Treatment recommendations are specific to patient groups. See disclaimer

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