Pregnancy and child

Flat coke for tummy bugs 'myth'

Doctors have warned that ‘flat Coke or lemonade could be dangerous to children suffering stomach bug,s’ the Daily Mail has reported. It said new NHS guidance warns that the‘myth that sweet drinks can rehydrate sick children can actually make symptoms worse.

This story is based on new guidelines issued by National Institute of Health and Clinical Excellence (NICE) for the treatment of children under five with gastroenteritis. One of the recommendations is that children with mild diarrhoea and vomiting be given water or rehydrating salt solutions and not carbonated drinks or fruit juice. NICE believes some of the most serious cases could be avoided if parents and GPs followed the best advice early on.

Most children with gastroenteritis can be safely managed at home. Parents and carers should follow the advice and keep children under five hydrated by encouraging fluid intake through water and milk, and to discourage fruit juices and carbonated drinks.

Parents who are concerned that their child is becoming dehydrated should have their child assessed by a healthcare professional. The guideline gives advice on the assessments recommended over the telephone and in face-to-face assessments.

Where did the story come from?

The news coverage is based on the release of new clinical guidance from the NICE, the organisation responsible for giving national guidance for the promotion of health and the treatment and care of people with specific diseases and conditions.

The guideline: Diarrhoea and vomiting caused by gastroenteritis. Diagnosis, assessment and management in children younger than 5 years , was commissioned by the Department of Health and is available online from the NICE website.

What kind of scientific study was this?

This is an evidence-based clinical practice guideline for healthcare professionals who care for children under five with diarrhoea and vomiting caused by gastroenteritis. It covers diagnosis, assessment of dehydration, fluid management, nutritional management and the role of antibiotics and other therapies. It also considers situations when care should be escalated from home to hospital.

The parts of the guideline that are relevant to the news story are as follows.

The guideline development team did not find any published studies that looked at the effectiveness of fluids other than ORS in the treatment of dehydration. One study did look at what was in a wide range of readily available fluids and commercially produced drinks including soups, juices, fruit-flavoured drinks and carbonated drinks. The analysis showed a wide range of sodium concentrations (ranged from 0.1 to 251 mmol/l), potassium concentrations (from 0.0 to 65 mmol/l), and osmolalities (ranged from 246 to 2000 mOsm/l) in the substances tested that included cola.

The high osmolality and unpredictable sodium and potassium content of many of these drinks suggest they could be harmful.

What were the main recommendations?

Recommendations for parents and carers to prevent the spread of infection

The guideline says that washing hands with soap (liquid if possible) in warm running water and careful drying is the most important factor 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, and 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 and should not swim in swimming pools for two weeks after the last episode of diarrhoea.

Managing sick children at home

The guidelines are not intended for direct use by parents or carers, but instead give recommendations to healthcare professionals on the advice to give them.

The guidelines recommend that parents of children being managed at home should be given a ‘safety net’. This is done by giving parents information on how to recognise ‘red flag’ symptoms of dehydration and how to get immediate help if red flag symptoms develop. The red flag symptoms of dehydration for children who appear to be unwell or to be deteriorating include altered responsiveness (e.g. if they are irritable or lethargic). Other symptoms of dehydration are decreased urine output (dry nappies). Pale or mottled skin with cold feet and hands is a sign of more serious dehydration and shock.

The healthcare professional should make arrangements for follow-up at a specified time and place if necessary.

The advice that healthcare professionals should give to parents and carers include:

  • telling them that most children with gastroenteritis can be safely managed at home,
  • diarrhoea usually lasts for 5–7 days and stops within two weeks, and vomiting usually lasts for 1–2 days and stops within three days.

Carers should be told how to recognise dehydration by looking out for such things as general appearance, responsiveness, decreased urine output, skin colour changes and temperature of arms and legs. More detail about how to care for a child after rehydrations and how fluid and food should be managed is published in the guideline.

The guideline lists three situations where parents and carers should contact a healthcare professional:

  • if symptoms of dehydration develop,
  • if symptoms do not resolve as expected, or 
  • if the child refuses to drink ORS solution or persistently vomits.

Selected recommendations for children with gastroenteritis include the advice for health professionals:

  • To perform microbiological investigations of faeces samples when blood infection is suspected, there is blood and/or mucus in the stool or if the child has impaired immunity (not routinely).

Some recommendations apply to children with diarrhoea without signs of dehydration. Here the advice is:

  • To continue breastfeeding and other milk feeds,
  • Encourage fluid intake,
  • Discourage drinking fruit juices and carbonated drinks (especially in children at increased risk of dehydration), and 
  • Offer low osmolarity oral rehydration salt solution (ORS) as supplemental fluid if the patient is at increased risk of dehydration

Some recommendations apply to children with clinical dehydration. For these the guideline advises parents:

  • to use 50 ml/kg for fluid deficit replacement with ORS over four hours in addition to maintenance fluids,
  • that the ORS solution should be given frequently and in small amounts,
  • to continue breastfeeding, and 
  • to think about supplementing ORS with usual fluids (including milk feeds or water, but not fruit juices or carbonated drinks) if the child refuses to take sufficient quantities of the ORS solution and do not have symptoms or signs of concern.

After the child is rehydrated, the team suggest that parents give full-strength milk straight away and re-introduce the child’s usual solid food and to avoid giving fruit juices and carbonated drinks until the diarrhoea has stopped.

What interpretations did the researchers draw from these results?

The researchers say that infective gastroenteritis is by far the most common cause for the sudden onset of diarrhoea, with or without vomiting. They say that a range of viruses, bacteria and other pathogens may be responsible. Viral infections account for most cases in the developed world.

They advise that the management of young children with gastroenteritis involves many considerations. The guideline is designed to resolve any debate or controversy regarding various aspects of clinical management.

They confirm there is evidence of considerable variation in practice in the management of children with gastroenteritis in      the UK.

What does the NHS Knowledge Service make of this study?

There is a popular belief that carbonated drinks such as cola or lemonade that have gone ‘flat’ can help settle stomachs. These guidelines say that the evidence does not support the use of carbonated drinks, lemonade or fruit juice as alternatives to commercially produced oral rehydration solutions (ORS). These solutions were considered the appropriate fluid for oral rehydration.

Parents and carers should follow this advice and keep children under five hydrated by encouraging fluid intake through water and milk, and to discourage fruit juices and carbonated drinks.


NHS Attribution