It's a common problem that can turn toilet time into a battleground - paediatrician, Kerry Robinson, suggests nipping it in the bud

Constipation can be frightening and if it's a painful experience, your child may well be put off going to the toilet, making the problem worse. But you can't blame your child. The problem stems from the fact that when it's difficult to do 'number two' he/she has to respond by straining harder than usual. If you don't take evasive action, your child's rectum could become distended and damaged, so do treat the problem seriously.

What's 'normal'

If your child isn't experiencing pain when passing a motion, you don't need to worry about variations in the number of times they perform each day. The frequency of bowel motion goes with age, so breastfed babies have about three bowel motions a day, bottle-fed babies about two. By the age of three, a child usually does one bowel motion per day, but this can vary a lot.

Once constipation sets in, it can be a vicious cycle

Faeces (poo) are stored in the rectum. This is a stretchy hollow tube just inside the anus. Nerves sense when the rectum is getting full and send a message to the brain that it's time to go. If a child finds it painful to pass motion, they'll ignore this signal. Eventually, the rectum will get so full of waste that only loose or watery poo manages to squeeze out. This will in fact be diarrhoea - but is actually caused by the constipation. Your child has no control over this, so they may have an accident and soil themselves.

Of course, once stools get hard, they're more difficult to pass. This can make the rectum distended and reduce the urge to go; making the constipation even worse.

What causes constipation?

• Not drinking enough - lots of people don't realise how important fluids are to keep things moving in the gut. Make sure your child is drinking lots of water or juice (not fizzy drinks)
• Not eating enough - the bowel needs something to work on
• Not eating enough of the right thing - the bowel needs fibre (roughage) to keep things moving through
• Medication - some medicines cause constipation. If your child is taking regular medication, check with your doctor to see if this could be the cause
• Withholding, as described earlier - when a child finds it painful to pass a motion and holds on instead because he/she too is frightened to go again. The pain can be caused by cracks in the delicate skin around the anus, which tears, when passing a hard motion. Withholding can also be due to emotional causes linked to family stress, or because the child has bad memories of potty training
• Age - children typically refuse to obey their parents at the ages of 2 - 3 years. This can all be bound up with potty training
• Excessive milk drinking in toddlers
• Lack of exercise
• Family history

Breakfast is a good trigger for the bowel - make sure it's not skipped. It may help to make it earlier so that there's more time to use the toilet before going to school. Give all the family wholemeal bread and encourage them to drink a glass of water or juice with each meal.

Recommended high fibre foods:

• Brown, granary or wholemeal bread
• Cereals such as Weetabix, Ready Brek, Frosted Wheats, Shreddies
• Wholemeal pasta, brown rice
• Baked beans and sweetcorn
• All fruit - leave skins on if possible
• All vegetables
• Biscuits - digestives, fig rolls, HobNobs

• Drink at least 1 ½ litres (2 ½ pints) of liquid every day (not the fizzy kind)
• Eat at least 5 portions of fruit or vegetables a day.

Beware though, children can easily become faddy about food so don't get too stressed about your child's diet. They're quick to sense the anxiety, and this will only compound the problem.

What can my GP do?

If changing your child's diet hasn't made any difference, your GP may offer laxatives. They work by making the stool softer or by stimulating the bowel. Your child may need to take them for some months but, combined with a good diet, this should get the bowel back into normal rhythm.

So remember:

• Lots of liquid, fruit, brown bread and rice
• And don't show you're worried - the anxiety will only work against you.