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Constipation About Duphalac®

About Duphalac®

What is DUPHALAC®?

Duphalac® is an effective medicine for constipation that can be used by all the family. The active ingredient of Duphalac® is lactulose, which helps to soften the consistency of stools so they are easier to pass.4

Why use DUPHALAC®?

Duphalac® has been trusted by generations for gentle and effective relief from constipation.3 It’s also a prebiotic, which means it can promote the growth of ‘good bacteria’ in the gut, which may improve the working of your bowels.4

Duphalac®, constipation relief that lasts.1,2

What is a prebiotic ?

Prebiotics serve as nutrients for beneficial micro-organisms (sometimes described as “good bacteria”) within the gut.10

Learn how prebiotics can lead to an improvement in the balance of the intestinal flora.4


How Does Duphalac® Work?

Duphalac® contains lactulose, which is a type of laxative called an osmotic laxative. It relieves constipation by increasing the amount of fluid in your bowels, to soften stools and make them easier to pass.

Prebiotic effect strengthens the growth of health promoting bacteria, like Bifidobacterium and Lactobacillus, whereas potentially pathogenic bacteria, like Clostridium and Escherichia coli may be suppressed.4


Lactulose is the main ingredient in Duphalac®. It’s not absorbed in the body but works in the bowel by drawing water into the intestine to make stools softer.4 Lactulose has been available for all the family since the 1960s, so its gentle and effective action is well-known.3,6


Duphalac® can be taken by:4







If you think your child has constipation, it is advisable to talk to your doctor!

Talk to your doctor or pharmacist if you:4

  • Are unable to digest a sugar called lactose (lactose intolerance). Lactose intolerance is a common digestive problem where the body is unable to digest lactose, a type of sugar mainly found in milk and dairy products.13
  • Are allergic to lactulose or any other ingredients of Duphalac®
  • Have ever had an allergic reaction to lactulose
  • Have diabetes (as lactulose may affect your blood sugar levels)
  • Have a rare health problem where the body cannot process a sugar called galactose (galactosaemia)4
  • Have unexplained tummy pain
  • Have a blockage caused by something other than constipation


Constipation can affect anyone in the family, but women and elderly are particularly at risk11,12


Duphalac® has been used to treat constipation for all the family for more than 50 years.3

Like all medicines, Duphalac® may cause side effects in some people, When you start taking Duphalac®, you might experience flatulence. This will usually ease off after a few days.4

If you find that the side effects don’t go away, or bother you, try reducing your dose. If you’ve experienced excessive fluid loss caused by vomiting or diarrhea, this may result in an imbalance of electrolytes (salts and minerals found in the body). If you think this may be the case, talk to your doctor.4

See the full Duphalac® range to find the right product and dose for you

It’s important that you check the leaflet that comes with Duphalac® to make sure you’re starting on the right dose. Ask your doctor or pharmacist if you’re not sure.

Take Duphalac® once or twice a day, After a few days the starting dosage may be reduced to a maintenance dose based upon treatment response.4

Aim to drink 6 to 8 glasses of fluid during the day whilst you’re taking Duphalac® to help ease your constipation.4

If you take Duphalac® for several days and there’s no improvement in your symptoms, see your doctor.

See the full Duphalac® range to find the right product and dose for you

If you forget to take your dose of Lactulose, don’t worry, just take your next dose at the usual time. It might help to set an alarm to remind you.14

See the full Duphalac® range to find the right product and dose for you

If you accidentally take an extra dose, don’t worry, it’s unlikely to harm you, but it is recommended that you either stop or reduce your dosage. You may get diarrhea and stomach pain, but this should go away after a few days. Talk to your doctor or pharmacist if you have any concerns.14

See the full Duphalac® range to find the right product and dose for you


The following side effects have been reported with Duphalac®:4

Very common (may affect more than 1 in 10 people)

  • Diarrhea

Common (may affect up to 1 in 10 people)

  • Flatulence
  • Abdominal pain
  • Nausea
  • Vomiting

Uncommon (may affect up to 1 in 100 people)

  • Electrolyte imbalance due to diarrhea

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