Diarrhoea and dehydration in children: care and warning signs

Diarrhoea is a common illness in children. Most episodes pass within days, but the loss of body fluid can become serious, especially in babies and young children. This article explains the causes, how to prevent dehydration, how to stop the illness spreading and when to see a doctor, using information from the NHS, the World Health Organization (WHO) and MedlinePlus.

1. Introduction

The WHO defines diarrhoea as three or more loose or liquid stools in a day, or more often than is normal for the person. Normal formed stools, and the loose pasty stools of breastfed babies, do not count ^[2]. The WHO calls it the third leading cause of death in children under 5 worldwide, and a leading cause of malnutrition in that age group, yet it is both preventable and treatable ^[2]. The NHS notes that diarrhoea and vomiting are common in adults, children and babies and usually settle within a few days, and that the advice is the same whether they occur together or separately ^[1].

2. Causes and risk factors

Most diarrhoea in children comes from an infection of the gut by bacteria, viruses or parasites. The WHO names viruses such as rotavirus and norovirus, bacteria such as E. coli, Salmonella and Shigella, and parasites as causes, and says rotavirus and E. coli are the most common across all age groups. These germs spread mostly through water contaminated with faeces, and also from person to person, through poor hygiene and through unsafe food handling ^[2]. Risk rises with unsafe drinking water, poor sanitation, unsafe food handling and malnutrition ^[2].

The NHS says most cases are a stomach bug or food poisoning. Less often, diarrhoea is linked to medicines, food intolerance or allergy, or other digestive conditions ^[1].

3. Signs and symptoms

Diarrhoea usually lasts 5 to 7 days and vomiting 1 to 2 days ^[1]. The most important danger is dehydration, which means the body has lost more fluid than it has taken in. MedlinePlus lists these signs in infants and young children ^[3]:

• Dry mouth and tongue
• Crying without tears
• No wet nappies for 3 or more hours
• Unusual sleepiness or drowsiness
• Irritability
• Sunken-looking eyes
• High fever

The WHO adds that a child with severe dehydration may be very sleepy or unconscious, drink poorly and have skin that goes back slowly when gently pinched ^[2].

4. Diagnosis

For dehydration, MedlinePlus says diagnosis involves a physical exam, a check of vital signs (such as heart rate and breathing) and a review of symptoms. Blood tests can measure body salts and kidney function, and urine tests can confirm dehydration and look for its cause ^[3].

5. Treatment and home care

The main aim is to replace lost fluid. The WHO explains that oral rehydration solution (ORS), a mix of clean water, salt and sugar, is a low-cost way to treat dehydration. Severe dehydration may need fluids given into a vein in hospital ^[2]. The WHO also says a course of zinc tablets shortens diarrhoea, so ask a doctor whether zinc is suitable for your child, and that nutritious food, including breast milk, should continue during illness ^[2].

The NHS gives these tips for children ^[1]:

• Offer small sips of fluid often, especially if the child is vomiting.
• Keep breastfeeding or bottle feeding. Offer smaller, more frequent feeds if the baby is being sick.
• Offer food if the child can eat. Avoid fatty or spicy foods.
• Avoid fruit juice and fizzy drinks, which can make diarrhoea worse.
• Do not dilute formula milk.
• Do not give anti-diarrhoea medicine to children under 12 or aspirin to those under 16.

6. Prevention and stopping the spread

The WHO lists safe drinking water, good sanitation, handwashing with soap, good food hygiene, exclusive breastfeeding for the first 6 months and rotavirus vaccination as ways to prevent diarrhoea ^[2]. The NHS adds these steps at home ^[1]:

• Wash hands often with soap and water.
• Wash soiled clothes and bedding separately on a hot wash.
• Clean toilets, taps and door handles daily.
• Do not share towels or cutlery.
• Keep the child off school until 2 days after symptoms stop.

7. Special groups

The WHO says children who are malnourished or have weakened immunity are most at risk of life-threatening diarrhoea ^[2]. MedlinePlus says infants and young children are at higher risk of dehydration because they are more prone to diarrhoea and vomiting ^[3]. The NHS advises getting advice early for any baby under 12 months who is unwell with diarrhoea or vomiting ^[1].

8. When to see a doctor

The NHS advises getting medical help if ^[1]:

• A baby under 12 months is ill, or a child stops feeding.
• A child under 5 shows signs of dehydration, or the signs continue after using oral rehydration sachets.
• Vomiting means fluids cannot be kept down.
• There is blood in the stools, or diarrhoea lasts more than 7 days.

Go to hospital urgently for blood in vomit, green vomit, a stiff neck, severe stomach pain, blue, grey or pale skin, severe difficulty breathing or confusion ^[1]. MedlinePlus lists confusion, fainting, little or no urine, fast heartbeat or breathing and shock as emergency signs of dehydration ^[3].

In an emergency, call your local emergency number (112 in India, 911 in the United States).

9. Conclusion

Diarrhoea in children is usually caused by an infection and often settles in days, but dehydration is the main danger. Small, frequent fluids, continued feeding, handwashing, clean water and vaccination protect children. Seek medical help early for babies, signs of dehydration or blood in the stool. Your doctor decides on treatment.