Toddlers Diarrhoea

My 2-year-old boy has loose bowel actions and is filling his diaper very frequently. He seems well and our doctor says he is growing ok. A number of tests have been done and none show a problem. What do you think is causing this?

Your son’s problem is quite common. Sometimes it is due to a persistent infection in the bowel and I imagine your doctor has sent off bowel actions to exclude this. One bowel infection that can be difficult to pick up in this way is due to a bug called Giardia and often treatment for Giardia is given even if it is not detected.
A persistent infection elsewhere in the body can also cause diarrhoea and one that is often hard to find just by looking at the child is a urinary tract infection. If not already done, it would be worth sending a urine sample to the laboratory to exclude infection.
As he is growing well it is unlikely that his gut is having difficulty in absorbing his food which is another cause of large quantities of bowel action. For the same reason and his young age he is unlikely to have inflammatory bowel disease such as Crohn’s Disease.
Sometimes an allergy to cow’s milk can cause diarrhoea. You might like to try him on a milk free diet (that is no milk, ice-cream, cheese, dairy products or manufactured products that contain milk such as bread and biscuits) for 3 weeks. Then put him back on his normal diet. If there is a dramatic improvement in the milk-free period followed by a resumption of diarrhoea when milk is taken then he probably has milk allergy. You should then consult a dietician for advice on a long-term milk free diet with calcium supplements. He will need to be on the diet for months before another milk challenge.
The commonest cause of persistent diarrhoea in an otherwise well toddler is called “Toddler’s Diarrhoea”. We do not know the cause of this condition and there is no treatment but the good thing is that it gets better by itself. Because there is no test for the condition, we like to exclude the known causes of diarrhoea that I have described before diagnosing Toddler’s Diarrhoea. The use of agents to slow down the bowel can be dangerous in that there is only a very narrow gap between the effective dose and the dose that is toxic in children. This makes it very easy to “poison” the child accidentally – a sorry outcome for a nuisance condition rather than a true health threat