Lactulose - oral

Patient Medicine Information
Why do I need this medicine?
Lactulose helps relieve constipation and maintain regularity of bowel movement.

It belongs to a group of medicines called osmotic laxative. Lactulose works by drawing water into the bowel which makes the stools softer so it can move out of the body more easily.

This medicine can also be used to treat hepatic encephalopathy (brain impairment associated with liver disease).
How do I take this medicine?
Take Lactulose exactly as directed by your doctor or according to the instructions on the label. Do not take more or less than instructed by your doctor.

You may take this medicine with or without food. Try to take it at the same time each day.

Lactulose is available as an oral solution in a bottle or sachet, or as a powder for oral solution.

If you have been given the oral solution in a bottle, use the measuring spoon or cup provided to measure out your dose. The oral solution may be mixed with a glass of water or fruit juice. Drink immediately after mixing.

If you have been given the oral solution in a sachet, you may take it undiluted or diluted in a liquid.

Lactulose also comes as a powder for oral solution. Empty the contents of the packet, dilute and and mix it with water. Stir to dissolve the powder evenly in the water. Drink the solution immediately.

Ensure adequate fluid intake (at least 6-8 glasses) while you are being treated with this medicine.

The dose of Lactulose will be decided by your doctor. Your doctor will advise you on the dose and course of your treatment depending on your condition.
What should I do if I have forgotten to take this medicine?
Take the missed dose as soon as you remember. If it is almost time for your next dose, skip the missed dose and return to your normal dosing schedule.

DO NOT double dose under any circumstances.

If you often forget to take your medicine, let your doctor and pharmacist know.
When should I not use this medicine?
Alert your doctor if you have the following conditions:
  • galactosaemia (a rare inherited disorder where the body cannot break down galactose, a type of sugar commonly found in breast milk and milk products)
  • blocked bowel caused by factors other than constipation
  • bowel diseases e.g. ulcerative colitis (inflammation of the large intestines), Crohn’s disease (long-term inflammatory disease of the digestive tract)
  • digestive perforation or at risk of digestive perforation
  • unexplained stomach pain
  • low galactose diet
as Lactulose may not be suitable for you.
What should I take note of while taking this medicine?
Inform your doctor if you have the following conditions:
  • diabetes
  • intolerance to lactose (type of sugar commonly found in milk and milk products)
  • Roemheld syndrome (stomach disorder causing certain heart problems such as chest pain and palpitation)
Let your doctor know if you are pregnant or breastfeeding.

Be sure to check with your doctor or pharmacist before giving this medicine to a child, elderly or those who are debilitated (a person who is physically or mentally weak usually due to illness or old age). Children, elderly and debilitated people may be more sensitive to the side effects.

If you are going for procedures such as proctoscopy and colonoscopy (examination of the bowel), inform your doctor that you are taking Lactulose.

Keep your appointments with your doctor. Your doctor needs to monitor your condition and check your response to the medication regularly. You may need to check your blood pressure and have routine blood tests (e.g. blood electrolytes) while you are being treated with this medicine. Your doctor will advise you about how often you need to have these tests.

What lifestyle changes should I make to improve my digestion?

A healthy, balanced diet and regular exercise are keys to helping intestinal bowel functions normally.

Follow a healthy diet plan by eating foods rich in fiber. Some examples of these foods are bran, beans, berries, whole grains, green and leafy vegetables, nuts, seeds, squash, and many other under this category. Reduce intake of foods such as milk, cheese, white rice, white flour, and red meat as they will contribute to constipation.

Constipation is also caused by lack of water in your body and mainly in stool. You should drink plenty of water to stay hydrated. Restrict the intake of caffeine-containing beverages such as coffee, tea and certain soft drinks.

Engage in physical activity like walking at least 30 to 60 minutes on most days of the week. If you have not exercised for a long time, start with light exercises such as slow walks. You will find that keeping to a regular exercise regimen is enjoyable and helps not only your muscles but also it stimulates the natural contraction of your intestines, making it easier to pass out your stool in your body. Speak to your doctor about what type of exercise would be suitable for you.
What side effects could I experience?
Lactulose may cause any of the following side effects: diarrhoea, stomach wind, stomach pain and cramps, nausea and vomiting.

Inform your doctor if any of these side effects do not go away or are severe, or if you experience other side effects.
Can I take this with other medicines?
Inform your doctor and pharmacist if you are taking any of these medicines:
  • hydrochlorothiazide (water pill or medicine for water retention)
  • amphotericin B (medicine to treat fungal infection)
  • neomycin (antibiotic)
  • antacids (medicines that reduce stomach acid production) e.g. aluminum hydroxide
This list does not include all medicines that may interact with Lactulose.

Always notify your doctor and pharmacist if you are taking any other medicines, including herbal tonics such as traditional Chinese medicines, supplements and medicines that you buy without a prescription.
What special dietary instructions should I follow?
Drinking plenty of liquids and eating fibre-rich foods such as fruits and vegetables can help relieve constipation.

Avoid alcohol.
How should I store this medicine?
Store in a cool, dry place away from the reach of children.

Do not refrigerate or freeze. Protect from light.

Medicines must not be kept past the expiry date.
This information is independently developed by MIMS based on lactulose - oral and is provided for your reference only. It is not a replacement for and should only be used in conjunction with full consultation with a licensed healthcare professional, the information provided by your pharmacist and/or the manufacturer of the medication. It may not contain all the available information you require and cannot substitute professional medical care, nor does it take into account all individual circumstances. Although great effort has been made to ensure content accuracy, we shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2022 MIMS. All rights reserved. Powered by
  • Dhactulose
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Sign up for free
Already a member? Sign in