Constipation in children

  • Constipation affects between 0.7 to 29.6% of children under the age of eighteen.
  • Almost two thirds of constipated children are thought to suffer from chronic functional constipation (CFC)
  • CFC is when there are no obvious structural or neurological cause for the constipation.

 How do you solve a problem you can’t see?

We look at the causes to find the solution.

Possible causes or contributers

Slow conveyor belt theory

  • In the first instance, the movement of the stool in the colon is slower than it should be. The medical term for this is slow colonic transit.
  • If you imagine your food travelling on a conveyor belt inside your body, you can imagine the conveyor belt moving really slowly. This causes the stool to take a long time to move through the system.
  • The longer the stool remains in the colon, the drier it will become, because there will be more time for the colon to extract water. By the time the stool reaches the end of the digestive system it will be hard to pass.
  • These children will benefit from lifestyle adaptations, diet modification and safe laxative treatment that could speed up the transit to some extent.


Closed door theory

  • Sometimes, the rate of transit of the stool in the colon is perfect, but when the stool must pass through the rectum, tension in the muscles surrounding the back passage can prevent the stool from passing comfortably. This is called obstructive defecation.
  • There is literally a mechanical obstruction of the rectum by the tight and tense pelvic floor muscles. this muscle is called Puborectalis.
  • Sometimes the tension occurs due to previous painful stools or constipation, and children start avoiding going to the toilet, because of the pain during defecation.
  • Stool withholding makes the problem worse, because not goin when you need to go causes abdominal pains and bloating.
  • These children could benefit from toileting education. Sitting correctly and giving your bowels enough time to empty will help to make toileting less painful.
  • In some instances, children with obstructive defecation might need bio-feedback training with a physiotherapist to help teach them to fully relax the back passage.



It is time to consult your doctor if *:

  1. Your child passes two or less stools in the toilet per week
  2. Your child has at least one leaking accident involving stool per week
  3. Your child shows signs of holding in stool
  4. Your child passes very large stools that block the toilet.
  5. A doctor finds a large mass of stool in the rectum of the child

*These criteria must be fulfilled at least once per week for at least two months before diagnosis and is adapted from the Rome III criteria.

It is also common that children with constipation strain when they go to the loo, complain of pain when they go to the toilet and have poor appetite. The conveyor belt is so full there is no space for food in the system…


In future blogs I will write on potty training, pelvic floor muscles and constipation and demystifying the big down under for children.

Happy parenting. This too shall pass.

What to do next?