Diarrhoea and constipation Dr Trisha Macnair Diarrhoea and constipation are both changes in the normal bowel habit, which affect all children occasionally.

In this article

What are the symptoms?

What causes them?

What's the treatment?

With diarrhoea, the child may open their bowels several times a day, passing watery or runny faeces. There can be a lot of wind and the diarrhoea may be 'explosive' or particularly foul smelling. Depending on the cause, the child may also experience abdominal pain, nausea and fever.

With constipation, the faeces may be hard and painful to pass. It can cause a tear in the delicate lining of the anal canal, which may lead to streaks of blood on the faeces. Because the bowels become overloaded with faeces, the sensation of needing to open them may be lost and the child can unintentionally soil themselves as the bowels overflow. This can cause both diarrhoea and constipation at the same time.

It's difficult to be specific about what constitutes a normal toilet habit. Many people think that once, or possibly twice, a day is normal, but there's a wide range. Breastfed babies may not pass faeces for several days but still be healthy. With children, it's important to take note of a change in habit.

There are many causes of diarrhoea and constipation.

The causes of constipation include dehydration (for example, following a feverish illness), a small tear or fissure in the anal canal (commonly, fear of pain inhibits the child from opening their bowels), psychological stress (for instance, unfamiliar surroundings or emotional trauma) and, rarely, a medical condition.

Diarrhoea may be caused by infection (such as gastroenteritis) or malabsorption problems, when food isn't taken in through the gut properly (such as food intolerance, coeliac disease and cystic fibrosis).

With diarrhoea, try to continue feeding your child as normal - don't starve them. Soups and high-carbohydrate foods are good choices. Offer drinks to avoid dehydration. Rehydration solutions can be used.

With mild constipation, increasing the intake of fluid and fibre (for example, stewed apples and root vegetables) may be enough. If this isn't effective, talk to your doctor, who may suggest lactulose to soften the faeces.

Always get medical advice for small babies. If problems persist, or your child seems unwell, see your doctor. Occasionally, persistent diarrhoea or constipation are a sign of more serious illness that needs to be investigated.

This article was last medically reviewed by Dr Rob Hicks in January 2008