Passer au contenu principal

Lactulose pour la constipation

Lactulose can take up to 48 hours to have an effect.

If you find the medicine makes you feel queasy, mix your dose with some water or fruit juice. Alternatively, take your doses with a meal.

Manger une alimentation saine, boire beaucoup d'eau et faire régulièrement de l'exercice doux peuvent tous aider à prévenir la constipation.

Find relief from constipation

Get expert healthcare advice from the comfort of home. Complete a quick online consultation, available 24/7, with your request reviewed by a UK-registered clinician. Next day delivery available on eligible treatments.

About lactulose

Type de médicament

An osmotic laxative

Utilisé pour

Constipation

Disponible sous forme de

Oral liquid medicine, liquid sachets

Constipation is a common problem. It can mean either going to the toilet less often than usual to empty your bowels, or passing hard or painful stools. Constipation can be caused by a number of things. Not eating enough fibre or not drinking enough fluid can cause constipation. Some conditions (such as pregnancy) can cause constipation, as can a lack of exercise or movement (such as being ill in bed) and some medicines.

Often, increasing the amount of fibre in your diet (such as by eating more fruit, vegetables, cereals, and wholemeal bread) and drinking plenty of water each day can effectively prevent or relieve constipation. You will have been recommended lactulose, a laxative, to help relieve constipation if you cannot increase the fibre in your diet or if this is insufficient. Lactulose works by drawing fluid into your bowel, which makes your stools softer and easier to pass. It is available on prescription, and it can also be bought without a prescription at pharmacies.

Lactulose also changes the acidity of the stools and this helps to discourage the growth of some germs (bacteria) present in the bowel. Because of this, lactulose is also prescribed for people with a liver disease called hepatic encephalopathy. If you have been prescribed it for this reason, ask your doctor if you need further information about the medicine.

Before taking lactulose

Some medicines are not suitable for people with certain conditions, and sometimes a medicine may only be used if extra care is taken. For these reasons, before you start taking lactulose it is important that your doctor or pharmacist knows:

  • Si vous êtes tellement constipé que vous pensez avoir une obstruction.

  • If you are unable to digest milk sugar (lactose intolerant).

  • If you have a condition called galactosaemia, where your body cannot process galactose.

  • If you are pregnant or breastfeeding. Lactulose is not known to be harmful to a baby, but while you are expecting or feeding a baby, you should only take medicines on the recommendation of a doctor.

  • If it is intended for a child. This is because laxatives should only be given to children on the advice of a doctor or healthcare professional.

  • Si vous prenez d'autres médicaments, y compris ceux disponibles à l'achat sans ordonnance, ainsi que des médicaments à base de plantes et complémentaires.

  • Si vous avez déjà eu une réaction allergique à ce médicament ou à tout autre médicament.

How to take lactulose

  • Before you start the treatment, read the manufacturer's printed information leaflet from the pack. It will give you more information about lactulose and will provide you with a full list of the side-effects which you may experience.

  • Take lactulose exactly as your doctor tells you to, or as directed on the pack. The usual dose for constipation in an adult is 15 ml (three 5 ml spoonfuls) twice daily, although the dose you are advised to take may be different from this as it will be adjusted to suit your needs.

  • If a doctor or healthcare professional has recommended lactulose for your child, check the label on the pack carefully to make sure that you give the correct dose for the age of your child.

  • Si vous oubliez de prendre une dose, ne vous inquiétez pas, prenez simplement la dose suivante lorsqu'elle est prévue. Ne prenez pas deux doses en même temps pour compenser une dose oubliée.

Tirer le meilleur parti de votre traitement

  • Lactulose can take up to 48 hours to act, so it may take two or three days before you feel the full benefit. However, if after several days you do not feel your symptoms are improving, or if they get worse, you should speak with a doctor for further medical advice.

  • It is important for you to drink plenty while you are constipated. Adults should aim to drink at least two litres (about 8-10 cups) of fluid per day. Most sorts of drink will do, but as a start, try just drinking a glass of water 3-4 times a day in addition to what you normally drink.

  • Essayez de manger un régime équilibré contenant des aliments riches en fibres tels que des pains et céréales complets, des fruits et légumes, du riz brun et des pâtes complètes. Si vous n'êtes pas habitué à un régime riche en fibres, il peut être préférable d'augmenter progressivement la quantité de fibres que vous consommez.

  • Garder votre corps actif vous aidera à maintenir votre système digestif en mouvement, alors essayez de faire de l'exercice quotidiennement.

  • You may wish to include some foods in your diet that contain sorbitol. Sorbitol is a naturally occurring sugar. It is not digested very well and draws water into your bowel which has an effect of softening stools. Fruits (and their juices) that have a high sorbitol content include apples, apricots, gooseberries, grapes (and raisins), peaches, pears, plums, prunes, raspberries and strawberries.

  • You can read more about how to prevent or treat constipation in the separate health information leaflets called Constipation (pour adultes) et Constipation chez les enfants.

Can lactulose cause problems?

Along with their useful effects, most medicines can cause unwanted side-effects although not everyone experiences them. The table below contains some of the ones which can occur with lactulose. You will find a full list in the manufacturer's information leaflet supplied with your medicine. Speak with your doctor or pharmacist if any of the following continue or become troublesome.

Lactulose side-effects

Que puis-je faire si je ressens cela ?

Excess wind (flatulence), tummy (abdominal) discomfort or cramps

These effects soon settle down as your body adjusts but if they continue or become troublesome, speak with your doctor or pharmacist for further advice

Se sentir malade (nausée) ou être malade (vomissements)

Try taking lactulose with meals, or mixing your dose with some water or fruit juice

Si vous ressentez d'autres symptômes que vous pensez être dus au médicament, parlez-en à votre médecin ou à votre pharmacien pour obtenir des conseils supplémentaires.

How to store lactulose

  • Gardez tous les médicaments hors de la vue et de la portée des enfants.

  • Conserver dans un endroit frais et sec, à l'abri de la chaleur directe et de la lumière.

Informations importantes sur tous les médicaments

Informations importantes sur tous les médicaments

Si vous achetez des médicaments, vérifiez avec un pharmacien qu'ils sont sans danger à prendre avec vos autres médicaments.

Ne prenez jamais plus que la dose prescrite. Si vous soupçonnez que vous ou quelqu'un d'autre avez pris une surdose de ce médicament, rendez-vous au service des urgences de votre hôpital local. Emportez le contenant avec vous, même s'il est vide.

Si vous subissez une opération ou un traitement dentaire, informez la personne effectuant le traitement des médicaments que vous prenez.

Ce médicament est pour vous. Ne le donnez jamais à d'autres personnes, même si leur état semble être le même que le vôtre.

Ne gardez pas de médicaments périmés ou indésirables. Apportez-les à votre pharmacie locale qui s'en débarrassera pour vous.

Si vous avez des questions concernant ce médicament, demandez à votre pharmacien.

Signaler les effets secondaires d'un médicament ou d'un vaccin

Si vous ressentez des effets secondaires, vous pouvez les signaler en ligne via le Site web de Yellow Card.

Questions fréquemment posées

Can diabetics take lactulose for constipation?

The article does not directly address whether lactulose is suitable for individuals with diabetes, but it mentions that certain medical conditions might require extra care. If you have diabetes, you should ensure your doctor or pharmacist is aware of your condition before taking lactulose.

Can lactulose be mixed with juice or other liquids?

Yes, if you experience feeling sick (nausea) or being sick (vomiting) when taking lactulose, the article suggests trying to mix your dose with some water or fruit juice.

Is it better to take lactulose with or without food?

The article suggests that if you experience nausea or vomiting, taking lactulose with meals might help. Otherwise, it doesn't specify whether it should be taken with or without food, focusing instead on taking it exactly as instructed by your doctor or as directed on the pack.

How long does lactulose stay in your system?

The article does not specify how long lactulose stays in your system. It primarily focuses on how long it takes for the effects to become noticeable, which can be up to 48 hours for a full benefit.

How often can you take lactulose solution?

For adults, the usual dose for constipation is 15 ml (three 5 ml spoonfuls) twice daily, but your doctor may recommend a different dose tailored to your needs. Always follow the specific instructions given by your doctor or on the pack.

Lectures complémentaires et références

Historique de l'article

Les informations sur cette page sont rédigées et examinées par des cliniciens qualifiés.
  • Prochaine révision prévue : 15 oct. 2026
  • 16 oct. 2023 | Dernière version

    Dernière mise à jour par

    Michael Stewart, MRPharmS

    Revu par

    Sid Dajani

Pharmacie en ligne, traitements et services de santé

Accès simple à des traitements fiables et à des services de santé en ligne.

Common conditions

Get help with common conditions through the NHS, without a GP appointment.

Book your free Pharmacy First appointment

Inscrivez-vous à la newsletter Patient

Votre dose hebdomadaire de conseils de santé clairs et fiables - rédigés pour vous aider à vous sentir informé, confiant et maître de la situation.

Veuillez entrer une adresse e-mail valide

En vous abonnant, vous acceptez notre Politique de confidentialité. Vous pouvez vous désabonner à tout moment. Nous ne vendons jamais vos données.