Diarrhoea is an  unpleasant side effect or symptom of any number of gastrointestinal problems in infants, young children and in teenagers. It can be described as frequent loose or watery stools, which may become urgent and explosive with limited warning.  It is commonly associated with a gastrointestinal infection, which in most instances will run its course with hydration fluids as the only treatment.  Infants are particularly vulnerable to dehydration and plenty of rehydration fluids are necessary.

Infective diarrhoea

For children with extended or severe infections such as Rotavirus, there may be temporary damage to the lining of the intestine, causing lactose intolerance for a couple of weeks following infection.  Lactose intolerance causes a characteristic watery, sometimes frothy stool causing a sore bottom and can be confirmed by your GP with a routine stool sample.  Infections are the most common cause of temporary lactose intolerance, which can also happen in other conditions where there is damage or inflammation of the gastrointestinal tract.

Non-infective diarrhoea

The causes of non-infective diarrhoea are many and varied, and a dietary assessment can be helpful in understanding if there is a food related cause such as food allergy or underlying coeliac disease. Weight loss is a common side effect of diarrhoea with malabsorption of nutrients a possibility if weight loss is prolonged or excessive.  Do see your GP to check for any underlying cause if weight loss is persistent.

Common causes of diarrhoea

Causes of diarrhoea in infancy and toddlerhood are very often infective in nature. Young children may also be sensitive to a variety of sugars in the diet other than lactose (milk sugar), including sucrose (table sugar) and fructose (fruit sugar) in fructose intolerance. In teens there can be many other causes including anxiety and emotional stress but also physiological changes which may cause changes in digestive and immune system function, causing food intolerance or irritable bowel syndrome.