Constipation in Children

What is constipation?

Constipation in children means:

• Difficulty or straining when passing stools (sometimes called motions, faeces or 'poo'). And/Or
• Pain when passing stools. And/Or
• Passing stools less often than normal. Note: there is great variation in the normal frequency of passing stools. Anything from three times a day to once every other day is common and normal. Less often than every other day means that constipation is likely. However, it can still be normal if when the child goes to the toilet he or she does not strain much, is not in pain, and the stools are soft and well formed.

It is useful to divide constipation in children into two broad categories:

1. Mild and/or temporary constipation that lasts just a few days. This is very common and can recur from time to time.
2. Chronic (persistent and severe) constipation. This is less common. Treatment is different to the more common temporary constipation. Details are given later in the leaflet.

What causes constipation in children?

Food and drink

A common reason why children become constipated is because:

• they do not eat enough foods with fibre (the roughage part of the food that is not digested and stays in the gut); and/or
• they do not drink enough.

Stools become harder, drier, and more difficult to pass if there is little fibre and fluid in the gut.

Holding stools in is a common cause

This means the child has the feeling of needing the toilet, but resists it. This is quite common. You may see your child crossing their legs, sitting on the back of the heels, or doing similar things to help resist the feeling of needing the toilet. The stool then gets bigger, and even more difficult to pass out later. There are a number of reasons why children may 'hold on' to stools.

• A previous stool that they passed may have been a struggle or painful. So, they try and put off doing it again.
• Their anus may be sore or have a crack (anal fissure) from passing a previous large stool. It is then painful to pass further stools. So, the child may resist the urge to pass a stool.
• They may have a dislike of unfamiliar or smelly toilets, such as at school or on holiday. The child may want to 'put things off' until they get home.
• Emotional problems may play a part in some children.

Medical conditions

A medical condition is an uncommon cause of constipation.

• Various diseases can cause constipation. For example, an underactive thyroid, and rare bowel disorders. Allergy to cows milk may be a factor in some children. Other symptoms are usually present if there is a 'medical' cause for the constipation. A 'medical' cause is unlikely if the child has developed normally, and is otherwise well.
• Some medicines can cause constipation as a side-effect.

How can constipation in children be prevented?

Eating foods with plenty of fibre and drinking plenty makes stools that are bulky, but soft and easy to pass out. Getting plenty of exercise is also thought to help.

Food and fibre

Ask your practice nurse for a list of foods high in fibre if you are unsure which foods contain fibre. Some examples are: fruit, vegetables, cereals, wholemeal bread. A change to a high fibre diet is often 'easier said then done', as many children are fussy eaters. However, any change is better than none. Have you tried such things as:

• A meal of jacket potatoes with baked beans, or vegetable soup with bread.
• Dried apricots or raisins for snacks.
• Porridge or other high fibre cereals for breakfast.
• Offering fruit with every meal.
• Perhaps do not allow sweets until your child has eaten a piece of fruit.

Another tip for when children are reluctant to eat high fibre foods is to add powdered bran to yoghurt. The yoghurt will feel grainy, but powdered bran is tasteless.

Drink

Encourage children to drink plenty. However, some children get into the habit of only drinking squash, fizzy drinks or milk to quench their thirst. These may fill them up, and make them less likely to eat proper meals with food that contains plenty of fibre. Try and limit these kinds of drinks. Give water as the main drink. However, fruit juices that contain fructose or sorbitol have a laxative action (such as prune, pear, or apple juice). These may be useful from time to time if the stools become harder than usual and you suspect constipation may be developing.

Some other tips which may help:

• Try and get children into a regular toilet habit. After breakfast, before school or nursery, is often best. Try and allow plenty of time so they don't feel rushed.
• Some kind of reward system is sometimes useful in younger children prone to 'holding on' to stools. For example, a little treat after each successful toilet trip. However, try not to make a fuss over the toilet issue. The aim is to be 'matter of fact' and relaxed about it.

Mild / temporary bouts of constipation in children and its treatment

Most bouts of constipation in children last just a few days. Many children strain to pass a large or hard stool now and then. It is of little concern, so long as a normal pattern soon returns. Treatment of temporary constipation is the same as for preventing constipation. That is, a diet with plenty of fibre, lots to drink, and perhaps a fruit juice which contains fructose or sorbitol. In some cases your doctor may advise a laxative for a few days.

With a temporary bout of constipation, the function of the lower bowel (rectum) is not altered. Therefore, you can stop any laxatives that are used once the stools become easily passed again. This may be after just a few days. This is different to chronic constipation (below) where the function of the rectum is altered and long-term laxatives are used.

Chronic (persistent and severe) constipation

Chronic constipation in children means that the constipation is severe and has lasted some time. It most commonly develops in children between the age of 2 and 4 years, but older or younger children can be affected. Symptoms and features of chronic constipation include:

• Recurrent times when the child is uncomfortable or distressed trying to pass a stool.
• The child soils their pants regularly with very soft faeces, or with faecal stained mucus. This is often mistaken by parents as diarrhoea.
• The child may also become irritable, not eat much, feel sick, have tummy pains from time to time, and may be generally out of sorts.
• A doctor can often feel a backlog of hard, lumpy stools when he or she examines the child's abdomen (tummy).

The following tries to explain how a child may develop chronic constipation, and the symptoms this may cause. In particular, why soiling is a symptom of chronic constipation.

• Normally, stools build up in the lower bowel (the lower part of the colon).
• When stools accumulate, they start to pass into the rectum (the last part of the bowel) which widens. This sends nerve messages to the brain which say 'you need to go to the toilet'.
• To go to the toilet then takes a little bit of effort to 'push out' the stools.
• However, if the messages are ignored, and the child 'holds on', then stools remain in the rectum.
• Large hard stools may then build up in the rectum.
• The rectum may then widen and enlarge (dilate) much more than normal.
• A very large stool may develop and get stuck (impacted) in an enlarged rectum.
• If the rectum remains enlarged then the normal sensation of needing the toilet is reduced. Also the 'power' to pass out a large stool is reduced (the rectum becomes 'floppy').
• More stools build up in the colon behind the impacted stool in the rectum.
• The lowest part of an impacted stool lies just above the anus. Some of this stool liquefies (becomes 'runny') and leaks out of the anus. This 'soils' the child's pants or bedclothes. Also, some softer, more liquid stools from higher up the colon may 'bypass' around the impacted hard stool. This also leaks out and soils the pants or bedclothes and can be mistaken for diarrhoea. The child has no control of this leaking and soiling.
• When a stool is eventually passed, because the rectum is distended and weakened, it simply fills up fairly quickly again with more hard stool from the backlog behind.

What is the treatment for chronic constipation in children?

A high fibre diet and lots to drink

This is described above and is usually advised in addition to laxatives.

Laxatives

Laxatives are usually prescribed if a child develops chronic constipation. The first aim is to clear any impacted (stuck) stool. This can usually be done fairly quickly with a good dose of a strong laxative. Sometimes a suppository or enema is needed to clear a large impacted stool. After the impacted stool has been cleared, it is important to continue with 'maintenance' laxatives as prescribed by your doctor. This can be for several months, even for up to two years. As the child takes laxatives every day, what happens is that:

• The child is likely go to the toilet and pass stools regularly. As they go to the toilet more often, the stools will be smaller and softer. So, the stools will be passed more easily. Any fear of going to the toilet to pass large and hard stools will ease.
• The enlarged rectum can gradually get back to a normal size and function properly again.
• Constipation is then unlikely to recur.

If laxatives are stopped too soon, a large stool is likely to recur again in the weakened 'floppy' rectum which has not had time to get back to a normal size and strength.

There are different types of laxatives which include:

• Bulk-forming agents. For example, bran, ispaghula husk, methylcellulose and sterculia. These make the stools softer but bulkier.
• Stool softeners. These work by 'wetting' and softening the stools. For example, docusate sodium (which also has a weak stimulant action).
• Osmotic laxatives. For example, lactulose and polyethylene glycol (brand name Movicol). These work by retaining fluid in the large bowel by osmosis (so less fluid is absorbed into the bloodstream from the large bowel).
• Stimulant laxatives. For example, senna or docusate. These act on the muscle in the wall of the bowel to 'squeeze' harder than usual.

A doctor will normally advise on which laxatives to use. However, it is quite common for a child to need two different types of laxatives for several months if one does not work alone. For example, an osmotic laxative plus a stimulant laxative. In time, the dose is gradually reduced and stopped. It is important to keep on with the treatment for as long as the doctor advises. Chronic constipation commonly recurs if treatment is stopped too soon.