Lactulose Solution


Available size:

300 ml 500 ml

Price £4.99

In stock


- +

Delivery Time


Expected delivery date:

Friday, 8 December 2023

If you order within:


Next Day Delivery

Next Day

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UK Registered Pharmacy

UK Registered

Discreet & Confidential

Discreet &

  • Overview
  • FAQ
  • Side Effects
  • Patient Information Leaflet
  • Reviews

What is Lactulose Solution

Lactulose Solution is a pure laxative that helps recognize constipation. It regulates bowel actions and also softens stools for a more neat experience.

How effective is Lactulose?

Lactulose is an effective laxative. With a place on the World Health Organization’s List of Essential Medicines, Lactulose is considered one of the most effective and safe medicines needed in a health system. It generally begins working after 8-12 hours but can take up to 2 days to improve constipation.

Can I buy Lactulose online?

Lactulose does not require a prescription for adult use, although you are very welcome to book an appointment with a health expert at Click Pharmacy to discuss how best to use this product. Lactulose can be purchased online and will be sent directly to you by Next Day Delivery. Multipacks are also available.

What dose should I choose?

Lactulose is available in bottles of 300 or 500ml.
The recommended dose for adults is usually 15ml, taken twice a day

For children aged 5 to 17 years, the usual dose is 5ml to 20ml twice a day

How should I take Lactulose?

Always take this medicine exactly as described in the Patient Information Leaflet or as your doctor or pharmacist have told you. Check with your doctor or pharmacist if you are not sure.
Take your doses at the same time each day. The dose may be given once daily, for example, during breakfast, or divided into two or three doses a day.
You can take Lactulose oral solution undiluted or diluted in some liquid. During the treatment with laxatives, you should drink sufficient amounts of fluids (approx. 2 litres per day, equal to 6-8 glasses). It can take 2-3 days until the desired effect has been achieved since Lactulose is not absorbed until it reaches the colon.
If you take more Lactulose than you should - In case of overdosage, you may experience diarrhoea and abdominal pain. Contact your doctor or pharmacist if you have taken more Lactulose than you should.

If you forget to take a dose of Lactulose, do not worry. Just take the next dose at the usual time. Do not take a double dose to make up for a forgotten dose.

If you stop taking Lactulose, The desired effect of the medicine may not be achieved. If you have any further questions on the use of this medicine, ask your doctor or pharmacist.

How does Lactulose work?

Constipation can be an unpleasant and painful experience. You may experience fewer bowel movements, and stools may have hardened.

There are many causes of constipation. Some of the most common include not enough water or fibre in your diet, consuming too many dairy products, not being active enough, stress, IBS, and other eating disorders.

Lactulose helps to relieve some of the symptoms by softening the stool and making it easier to pass. It achieves this by drawing water into the bowel. Lactulose is not absorbed by the body.

How long do I need to take Lactulose to work before I notice a difference?

Lactulose should take effect within 1-2 days. In the event you do not feel better or if you feel worse after 3 days, then consult your doctor.

What are the side effects of Lactulose?

Like all medicines, this medicine can cause side effects, although not everybody gets them. The following side effects have been reported with Lactulose:

Very common (may affect more than 1 in 10 people):
- Flatulence (wind), especially during the first few days of treatment. This usually disappears after a couple of days.
- When a higher dose than recommended is used, you may experience abdominal pain.

Common (may affect up to 1 in 10 people):
- Nausea (feeling sick)
- Vomiting
- When a higher dose than recommended is used, you may experience diarrhoea (sometimes including electrolyte imbalance).

Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. This includes any possible side effects not listed in this leaflet. 

What is the difference between Lactulose and Glycolax/Citrate of Magnesia?

Citrate of Magnesia is a quicker laxative that works within a few hours. It has some unpleasant side effects and is not recommended for more than 1 week of use.

Glycolax is based on polyethylene glycol. It takes 1-3 days to become effective.

When shouldn’t I use Lactulose?

Do not take Lactulose under the following circumstances: 

- if you are allergic to Lactulose or any of the other ingredients contained in this medicine. 
- if you suffer from galactosaemia (a severe genetic disorder where you cannot digest galactose),  acute inflammatory bowel disease (like Crohn's disease or ulcerative colitis), blockage in your bowel (apart from normal constipation), digestive perforation or risk of digestive perforation or unexplained abdominal pain.

Warnings and precautions:
Talk to your doctor or pharmacist before taking Lactulose. Please tell your doctor before taking Lactulose if you suffer from a gastro-cardiac syndrome (Roemheld syndrome).
If you have symptoms like excess gas in your bowels or bloating after using it, stop the treatment and consult your doctor. In these cases, your doctor will supervise the treatment carefully.
Long-term use of unadjusted dosages (exceeding 2-3 soft stools per day) or misuse can lead to diarrhoea and disturbance of the electrolyte balance. If you are an elderly patient or a patient in bad general condition and take Lactulose for a more than 6 months period, your doctor will regularly check your blood electrolytes. During the treatment with laxatives, you should drink sufficient amounts of fluids (approx. 2 litres per day, equal to 6-8 glasses).

Children and adolescents:

Lactulose should not usually be given to infants and smaller children as it can disturb the normal reflexes for passing stools. In special circumstances, your doctor may prescribe Lactulose for a child, infant or baby. In these cases, your doctor will supervise the treatment carefully.

Other medicines and Lactulose:
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicine.
Lactulose may increase the loss of potassium caused by other drugs (e.g. thiazides, steroids and amphothericin B). Use of cardiac glycosides (e.g. digoxin) along with Lactulose can increase the effect of the glycosides by decreasing potassium in the blood. With increasing dosage, a decrease of pH value in the colon is found. Therefore, drugs which are released in the colon pH-dependently (e.g. 5-ASA) can be inactivated.

Lactulose with food and drink:
Lactulose can be taken with or without food. There are no restrictions on what you can eat or drink.

Pregnancy, breast-feeding and fertility:
If you are pregnant or breastfeeding, think you may be pregnant or are planning to have a baby, ask your doctor or pharmacist for advice before taking this medicine.

Driving and using machines:
Lactulose will not affect your ability to drive safely or use machines.

Important information about some of the ingredients of Lactulose:
Lactulose may contain small amounts of sugars (lactose, galactose or epilactose). If you have been told by your doctor that you have an intolerance to some sugars, contact your doctor before taking this medicinal product.
Lactulose may contain more than 5 g lactose/galactose/epilactose, depending upon the dose taken. This should be taken into account in patients with diabetes mellitus. 15 ml of Lactulose contains 42.7 KJ (10.2 kcals) = 0.21 BU. 

Can children use Lactulose Solution?

Lactulose Solution is not suitable for children under the age of 14 years old. However in some cases it has been prescribed to children under the age of 14 years old.

Who should not use Lactulose Solution for treating symptoms of constipation?

Although Lactulose Solution does not usually cause any harm, it is not suitable for everyone to use. You should not use Lactulose Solution if you have any of the following:

  • Lactose intolerance
  • Galactosaemia
  • Diabetes

What is the difference between Lactulose Solution and Duphalac?

While both Lactulose and Duphalac are used for the treatment of constipation, the main difference is branding. Duphalac is the branded version of Lactulose making it cost more.

How should I measure the right amount of Lactulose Solution?

You should use the plastic cup provided with the medication to measure out the correct amount of solution.

Can I drink alcohol while taking Lactulose Solution?

Yes, it is safe to drink alcohol with Lactulose Solution. There is no evidence to suggest that alcohol interferes with the way Lactulose Solution works.

After using Lactulose Solution, you are likely to experience a number of side effects. These side effects are often mild and disappear over time. Common side effects and how to overcome them include:

  • Diarrhoea: drink plenty of fluids to prevent dehydration
  • Bloating: take Lactulose Solution between meals
  • Feeling sick: mix your dose of Lactulose Solution with water or a fresh fruit juice
  • Vomiting: drink plenty of liquids to ensure you are not dehydrated
  • Stomach pains: eat smaller meals and avoid rich spicy meals

If any of these side effects worsen, you should stop using Lactulose Solution and seek medical advice from a GP or pharmacist as soon as possible.

Always read the patient information leaflet before starting your treatment. The patient information leaflet can be  found here.

Authored by

Last reviewed 11 April 2023

Superintendent Pharmacist GPhC No.2220953

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