Constipation in children

Constipation is when your child has hard and/or infrequent poo (bowel motions, stool). Constipation often starts after one hard poo has caused pain, and so your child tries to avoid pain the next time by holding on and not going to the toilet, resulting in a vicious cycle.

Key points

  • Constipation in children is very common affecting up to 30% of children.
  • It is most common in 2 to 4-year-olds when they are potty training.
  • Most cases are what is called functional, and not due to anything serious. However, if your child has constipation that doesn’t go away, see your doctor.
  • If left untreated, constipation may cause your child to ignore the urge to poo (known as 'stool withholding') due to pain and/or distress associated with this.
  • If your child is on laxatives or stool softeners and not getting better, seek further help. 

Common symptoms of constipation in children

A child with constipation may:

  • move in a way that suggests they are holding in their poo, such as standing on tiptoes and then rocking back on the heels of the feet, clenching buttocks muscles, and other unusual, dance-like behaviours
  • cry, strain or show other signs of pain when having a poo or trying to have a poo
  • have hard, dry or small poo (looks like pebbles)
  • complain of stomach pain or cramps  
  • experience urinary tract infections and bedwetting  
  • poo in their pants. 

In most children constipation lasts a short time and is not serious. But for some children, it can cause ongoing discomfort. 

What causes constipation in children?

Constipation is caused by poo spending too much time in the lower bowel, where water is absorbed from the poo, making it hard and dry. Hard, dry poo is more difficult for the muscles in the bottom to push out of the body.

Cause Description
Ignoring the urge
  • Children most commonly develop constipation as a result of holding in poo
  • The may do this because they are feeling stressed about potty training, are embarrassed to use a public bathroom, do not want to interrupt playtime, or are fearful of having a painful or an unpleasant poo
  • Constipation in children is often caused by a poor diet that is high in fat and refined sugar (sweets, cakes, biscuits) and has too little fibre
  • Fibre helps the poo stay soft so it moves smoothly through the gut
  • Children between 4 to 18 years need about 18 to 28 grams of fibre a day
  • Fruit (fresh and dried), vegetables, whole grain cereals and bread, nuts and lentils are good sources of fibre
  • Dehydration can make constipation worse
  • It is often as a result of drinking too little fluid, or losing too much fluid such as by vomiting or excessive sweating
Changes in routine
  • Changes in the usual time of meals, as well as changes in their daily toileting routine (for example when on holiday) can cause your child to become constipated
Some medicines
  • A number of medicines can cause constipation as a side effect, for example, medication for pain, antacids, iron supplements.

Constipation in babies

It can be difficult to know if a baby has constipation because there is such variation in the firmness and frequency of poo in babies.

  • Breastfed babies may have a poo following each feed but some breastfed babies only poo every 7 to 10 days.
  • Babies fed formula tend to poo at least every 2 to 3 days. 

It is common for babies to strain a lot when they poo. As long as their poos are soft, they aren’t constipated. 

How to prevent constipation in babies

Constipation is often caused by changes such as weaning from breastmilk or other types of milk. To ease constipation in babies:

  • try increasing the amount of water your baby drinks, by offering small amounts of water between feeds
  • for bottle fed infants, consider trying out different infant formulas to find one that makes poo softer and easier to pass. 

How to prevent and ease constipation in children

Try simple measures first 

  • Increase the fibre content of your child's diet by giving your child more fruit (either fresh or dried) and vegetables. Cut fruit into chunks and offer this at every meal. 
  • Limit foods that have little or no fibre, such as ice cream, cheese, meat and processed foods.
  • Increase the amount of water your child drinks daily by giving them water at each meal time and extra water when it is hot.
  • Encourage a regular toileting routine such as sitting on the toilet for 5 minutes, once or twice a day.
  • Encourage daily exercise and physical activity. This helps stimulate normal bowel function.
  • For children over 12 months of age, try giving them one glass of undiluted apple juice or KiwiCrush (a kiwi fruit drink). 

Medications (laxatives)

Medications used to treat constipation are called laxatives. Treatment with a laxative is needed if the simple measures above do not work well. 

  • Laxatives usually work by softening the poo.
  • Some help the bowel push out the poo by stimulating the nerves in the bowel.

Your doctor or pharmacist will advise you on a suitable laxative for your child. Children should take medication until their bowel habits are normal for an extended period of time and they have overcome their holding behaviour. If treatment is stopped too soon, a child will likely become constipated again.

When to see your doctor about your child's constipation

You should take your child to the doctor if any of the following apply:

  • the simple measures above haven't worked
  • your child has been constipated for a long time
  • your child has tummy pain
  • your child is  pooing their pants (soiling).

If left untreated, constipation in children can lead to:

  • faecal impaction, where hard poos pack the intestine and colon tightly, and the normal bowel action cannot push the poo out.
  • this can lead to faecal incontinence, where children over the age of 4 years regularly poo their pants. In most cases faecal incontinence develops as a result of constipation that has been ongoing for some time. 

If your child has ongoing problems with toileting your doctor may refer them to a paediatrician or continence nurse. 

Learn more

The following links provide further information on constipation in children:
Constipation Kidshealth NZ
Constipation Ministry of Health, NZ
Faecal incontinence Continence NZ
Constipation in children Patient Info UK


Constipation in children for health professionals  Starship NZ
Constipation in children and young people; NICE Clinical Guideline (May 2010)
Childhood constipation Auth MK, Vora R, et al; BMJ. 2012 Nov 13;345:e7309

Credits: Editorial team. Last reviewed: 12 Aug 2016