Health & Fitness

What could be causing my son’s diarrhoea?


Q: My two-year-old son has been having daily episodes of diarrhoea for the past three months. He stopped breastfeeding at six months and is currently on the family diet. He does not seem to be having any tummy pain but the constant diarrhoea is a concern. He also gets lots of foul smelling gas. His growth is good and he is thriving in all other aspects. He has been tested for infections many times and nothing significant is found. He has received his rotavirus vaccine and the rest of his immunisation is up to date. What could be the problem?


Your son has chronic diarrhoea, which refers to diarrhoea that has been present for more than three weeks. Usually, determining the cause can be difficult and requires several lifestyle changes to pinpoint the culprit.

Possible causes of chronic diarrhoea in a young child

Infections of the digestive tract


Germs such as bacteria or viruses can cause diarrhoea in a child. Usually, this can be from contaminated water or food. Poor food hygiene and storage practices can also have a child having constant tummy problems. This includes keeping cooked food at room temperature for prolonged periods or not warming it appropriately before feeding.

In addition, eating practices such as drinking unpasteurised/unprocessed milk or food with raw eggs can cause your child to get diarrhoea causing germs. In addition, small children pick up germs on a daily basis from touching objects such as shoes, dustbin etc.

Toddler’s diarrhoea

This is a condition in which preschool children have multiple episodes of diarrhoea daily. The stool gets more watery as the day progresses. Usually, the stool contains mucus and undigested food products. The child will have a normal appetite and will not necessarily report pain. It is thought to be due to too much sugar in the child’s diet. (Concern has been raised about sweetened juices). Children with toddler’s diarrhoea are healthy and gain weight as expected despite the regular diarrhoea.

Gluten intolerance

This is a protein found in wheat, barley and rye. This constituents most children’s foods such as cookies, cakes, pasta and bread. Usually, children with gluten intolerance cannot tolerate these foods and most parents report bloating and diarrhoea after their children eat these products.

Food allergies

Some children may develop allergies to food items on the family diet. This includes allergy to beans (including soya products), eggs, milk and fish. Ingestion of these foods can lead to recurrent diarrhoea. Itchy skin rashes may accompany allergies.

Lactose intolerance

This is the inability to digest milk products due to lack of essential digestive chemicals in your child’s body. Children with lactose intolerance develop bloating and loose motions after ingesting milk or food items with milk.

Fructose/sucrose intolerance

Fructose is a sugar found in fruits, fruit juices, honey and enriched corn syrup. Fructose is often found in commercial children’s drinks. Sucrose is found in table sugar. Some children are not able to absorb these sugars and this leads to chronic diarrhoea.

Inflammatory bowel disease (IBD)

This is a condition in which the intestines get inflamed leading to diarrhoea (often bloody) and pain. The two main types of IBD are Crohn’s disease and ulcerative colitis. These disorders can affect children at any age (However, they are more common in adolescence). This is not a likely cause of diarrhoea in your baby.

Hirschsprung's disease

This is a condition in which the lower part of the large intestines does not have nerves that would allow it to process stool properly. It often requires surgery to treat.

Neuroendocrine tumours

These are rare tumours of the digestive system usually found in adults and older children. The tumours produce chemicals that can cause diarrhoea. However, most of the time, these tumours are accompanied by other features of hormonal imbalance.


Over-usage of laxatives can lead to diarrhoea. Some parents have unwittingly caused diarrhoea in their children by giving them daily doses of oil products such as glycerine.

Overflow diarrhoea

Children with long-standing constipation may develop episodes in which loose stool may flow out of the overloaded colon.

What to do

Have your child reviewed by a paediatrician for a full physical examination. Discuss the different possibilities that may be contributing to your son’s condition.

If there are no features of infection or congenital/hormonal problems, then try to see if you can effect some lifestyle changes to try and solve the puzzle of what is causing the diarrhoea.

Practise strict hand washing protocol in your household. The child’s hands should always be washed before feeding and after using the bathroom. Similar practice should be done by all those caring for the child.

Always wash fruits and vegetables before feeding them to the child. Keep cooked food in the refrigerator. Always heat it thoroughly before feeding it to your child. Do not give your child raw food products such as unprocessed milk and eggs.

Identifying food culprits. With the guidance of your paediatrician remove possible culprits from your child’s diet then reintroduce them to identify food products that your child may not be tolerating

Eliminate sweetened drinks from your child’s diet

Avoid giving your son medication to stop diarrhoea. These are not recommended for use in children.

Finally, remember to always keep your son well hydrated. Keep a few sachets of oral rehydration salts in the house in case of severe episodes of loose stool.

Urgent review

Children with diarrhoea can sometimes develop complications.

Take your child for urgent review with his doctor if he develops dehydration (characterised by excessive thirst, dry mouth, failure to pee as expected), bloody or black stool, fever, irritability, or becomes very drowsy.

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