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Hem Children with constipation – do microlax and lactulose help?

Children with constipation – do microlax and lactulose help?

Constipated child sitting on the toilet, pushing

This post is also available in: Svenska

Facts and advice about constipation in children Written by pediatricians for parents. Most children become constipated at some point. Learn how to recognize the symptoms of constipation and how to treat and prevent the problem. Do drugs work in children? Are there any home remedies that could help?

Read more about baby poop – what is normal and what is not, in this post.

Symptoms of constipation

Children with constipation sometimes find it difficult to poop or find that their poo is hard. Many have stomach aches, sometimes associated with mealtime, sometimes even otherwise. Some children experience pain in the bum, perhaps because the hard stools have caused a tear upon passing. In some cases of constipation, some children may feel sick. If the constipation is really bad, they may even vomit. Loss of appetite and whininess is also common.

Constipated diarrhoea

Fecal traces on underwear, or stool leakage (aka fecal incontinence), is usually the result of constipation. Sometimes there is such a large mass of poo stuck in the colon that the pressure forces some poo to seep through. This leads to smeared underwear. This also makes it difficult to detect constipation, because everything that comes out is so loose.

Fresh blood in the stool during constipation

Anal fissure is a tear in the rectum opening caused by passing a hard stool. As a result, there is often quite a lot of pain and fresh blood in the toilet. It’s not dangerous, even if the blood looks dramatic. However, the child undoubtedly needs constipation treatment. Pain-relieving ointment to the rectum opening before toilet visits can also help. Go to a medical center when convenient.

When an anal fissure heals, a small mucosal flap may form in the rectum opening. This doesn’t bother the child at all and it does not require medical attention.

The vicious cycle of constipation

When the stool becomes hard and thus difficult to poop, children will avoid going to the toilet. The stool remains in the intestine and subsequently, the colon mucosa absorbs more fluid from the stool. This makes the stool even harder and even more difficult to pass. Once the child tries to poo, it hurts even more. So the child will hold on even longer. A vicious cycle is occurring.

In a child who is not constipated, the rectum is empty. When it is filled with fecal matter, signals are sent to the brain that it is time to poop. In a constipated child, there is feces in the rectum most of the time. The gut sends signals to the brain, and when it is not possible to poop, the signals are interpreted as pain instead. Or your gut gets tired of sending signals that don’t lead anywhere and thus the child stops feeling the urge to poo.

A good film (in English) that shows the vicious circle of constipation and how constipated diarrhea occurs.

Treatment against constipation

The aim of long-term treatment against constipation is to break the vicious cycle and to allow the signalling system between the gut and brain to recover. These processes take time, generally several months. It is therefore important to continue treating constipation until your child has developed confidence and a rhythm in pooping. Do not stop after a week or two even if your child poos every day.

In case of mild constipation, dietary changes may be sufficient. Obviously, your child needs to embrace these dietary changes. Picky eaters, however, may need to skip this step and be given medication right away.

Foods that help relieve constipation

Prunes or pear purée

The most classic household remedy for constipation is probably prunes. It works quite well against milder constipation. Of course, it’s easier said than done! Imagine giving wrinkly prunes to a discerning preschooler. But for babies who eat canned food, you can try giving prunes and pear purée.

Whole grains and high-fiber food

High-fiber food is usually recommended for constipation. For children, fiber-rich, moist fruits such as well-ripened pears, plums and apples tend to help. On the other hand, dry fibres, as in whole grain products, can have the opposite effect if your child doesn’t drink a lot of water concurrently. Try it out.


Many people try a dairy-free diet to help relieve constipation. In isolated cases, it works. It’s assumed that the child has a form of cow’s milk protein allergy. In the vast majority of cases, it doesn’t help. And if that’s the case, it’s important to start drinking milk again.

Read more about cow’s milk protein allergy here.

Toilet routines to treat and prevent constipation

For children who have stopped wearing diapers, it is good practice to introduce a toilet routine. Allow the child to sit 10 minutes on the potty /toilet twice every day. Preferably after meals when the intestine has an easier time emptying itself. Some toddlers just want to poop in their diapers for a long time. Then let them do that, if that’s possible. Let them sit on the potty with their diaper on. The squatting position and floor support can help with their bowel movements.

Read more about potty training and toilet routines here.

Medicines for constipation

If dietary changes and toilet routines do not help, the child needs medication for constipation. It is extremely common for children to take medications for constipation at some point during childhood. And some may need it for many years.


Lactulose is a liquid medicine for constipation. It consists of long sugar molecules that are not absorbed into the blood stream but instead, settle in the intestine. There, the lactulose molecules extract water from the intestinal wall and the stools become looser. Lactulose tastes sweet and therefore tends to be easy to give to most children.

Lactulose is available without a prescription at a pharmacy. A common dosage to start with is 5 ml twice daily, reducing or increasing the dose according to results. The Bristol stool scale, a stool classification chart, is great to use to deceide whether you need to increase or decrease the dose. Preschoolers usually find it quite fun.

View and download the Bristol stool scale here.

A common but harmless side effect of lactulose is gasiness, which can cause stomach aches. Lactulose is harmless and can be used for many years without the intestine becoming “dependent” or damaged. Due to gasiness, Lactulose is not usually favoured in schoolchildren and teenagers. If your child needs constipation treatment longer than three months, seek medical advice to rule out underlying cause.

Movicol, Omnilax, Forlax etc (Macrogol)

Macrogol has many different brand names. They are sold as powder in sachets that dissolve in water. Some brands have the junior sachets that contain half the amount as an adult sachet. Of course, you could just as well buy the adult sachets and use half as much.

Macrogol is a type of fiber that settles in the intestine and attracts fluid so that the stool becomes soft. It is effective and generally doesn’t have gassiness as a side effect. The disadvantage is that it can be difficult to get children to take the solution.

The different varieties taste a little different. Movicol has a salty taste that many people do not like, and that cannot be hidden by juice or similar liquids. Omnilax or Forlax do not have the salty taste and are usually better tolerated.

An adult sachet or 2x junior sachets is usually a good starting dose for school-age children. At pre-school age, a junior sachet or half an adult sachet is a good starting dose. Increase or decrease dose according to the Bristol stool scale as advised. These medicines are slow acting and you do not have to be prepared to go to the toilet immediately after drinking them. Defecation becomes easier the next day.

Lactulose is harmless and can be used for many years without the intestine becoming “dependent” or damaged. If your child needs constipation treatment longer than three months, seek medical advice to rule out underlying cause.


If your child has severe constipation and acute stomach ache, an enema might be helpful. An enema is a medication that is inserted into the rectum. This will hopefully lead to rapid bowel movement.


Klyx is an efficient and fast-acting enema available without a prescription at pharmacies. For children aged over 1 year, who are free from fever, in good overall health, and are experiencing abdominal discomfort suggestive of constipation, you may consider administering a 120 ml Klyx enema in a home setting. It is often rapid and effective. But it’s common for the symptoms to reoccur in the near future. Therefore, you often need make lifestyle and dietary changes as well. Sometimes even, medication daily for a period.


Microlax is a small microenema that works by irritating the intestinal mucosa and thus encouraging the stools to come out. It’s often effective, but stings and hurts many children. I recommend you choose Klyx instead.


Resulax is also a small microenema, and unlike Microlax, it does not sting. It is a good alternative to Klyx. Many find it easier to insert into the rectum as it is smaller and smoother.

Common causes of constipation in children

Constipation commonly arises due to a change of some kind eg. diet, environment etc and not commonly because of any underlying disease. During childhood, three periods of constipation are most commonly seen.

  1. First, transitioning from breast milk to formula, or from breast milk/formula to solid food.
  2. Then, when a child stops using diapers.
  3. Then, when a child starts school. Many children do not want to poo in school. Often because the toilets are untidy, toilet paper is missing, the doors cannot be locked properly, or that other children will bang on the door or disturb them. We can all relate, right? There’s a lot to fix here!

Other changes may include travel, stressed periods and common infections. The latter affects the intestine in several ways. Infections can change the intestinal flora. This is especially the case for gastroenteritis. Also, children usually eat and drink less when they are sick. This combination, together with fluid loss in the form of vomiting, diarrhoea, fever or increased breathing, results in drier and harder intestinal content.

When should I seek medical care for my child’s constipation?

Severe, acute problems, or palpable abdominal pain that does not improve after Klyx, needs to be examined by a doctor the same day.

Read more about abdominal pain in children in this post.

Constipation that isn’t resolvable at home, or that requires treatment for more than three months, requires a doctor’s appointment. Go to your local medical center or pediatrician’s office. Tell the medical staff that you are giving treatment for constipation and for how long. They should be able to take over from here.

Read more:

Stomach pains in children – is it the appendix and what to do?

Baby poo – what is normal and what is not? Green poo and slimy poo – what does this mean?

Milk protein allergy, cow’s milk allergy, milk allergy in babies and children

Potty training – when to stop using diapers and how to become diaper-free.

Lactose intolerance in children – symptoms and tests

Incontinence – treatment for bed wetting and daytime wetting in children

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