Duphalac: Medical Uses, Mechanism of Action, Administration, Precautions, Side Effects and Interactions

It can help increase the number of bowel movements per day and the number of days you have a bowel movement.

Lactulose is a colonic acidifier that works by increasing the water content in the stool and softening the stool. It is an artificial sugar solution.

The lactulose type is a special sugar-like laxative that works similarly to the saline type. However, it produces results much more slowly and is often used for the long-term treatment of chronic constipation.

Lactulose can sometimes be used to treat certain medical conditions to reduce the amount of ammonia in the blood. It is available only with a prescription from your doctor.

Duphalac belongs to a group of medicines known as laxatives. Pregnant women can take it. It works by increasing the amount of water and stool in the intestine, promoting regular bowel activity.

Duphalac can also treat portal-systemic encephalopathy (ESP), also known as hepatic encephalopathy (a brain disease that occurs when the liver is not working correctly. Symptoms are caused by too much ammonia in the blood. ).

Duphalac can be used when loose stools are considered a medical benefit (hemorrhoids, anal surgery). It is available as a generic and brand product.


Your doctor or pharmacist may have prescribed or recommended Duphalac for another reason. There is no evidence that Duphalac is addictive. Symptoms of an overdose are likely to be diarrhea and abdominal cramps.

The ingredients

Every 15 ml of Duphalac contains 10 g of lactulose as the active ingredient, plus 1.5 g or less of galactose, 0.9 g or less of lactose, 0.7 g or less of epilactose, 0.3 g or less of tagatose and 0.1 go less fructose.


It is used orally for constipation and orally or rectally for hepatic encephalopathy. It usually starts working after 8 to 12 hours, but it can take up to 2 days for constipation to improve.

Common side effects include abdominal bloating and cramps. There is a potential for electrolyte problems due to diarrhea it produces. When used during pregnancy, no evidence of harm to the baby has been found. It is classified as an osmotic laxative.

Lactulose was first manufactured in 1929 and used medically since the 1950s. It is on the World Health Organization’s Essential Medicines List, the safest and most effective medicines needed in a healthcare system.

It could be purchased for approximately US $ 0.16 per 15 ml of syrup (10 g of lactulose) in several countries in 2015.

In the United States, the cost of this amount is approximately $ 0.63. Lactulose is made from milk sugar lactose, which comprises two simple sugars, galactose, and glucose.

Medical uses


Lactulose is used in treating chronic constipation in patients of all ages as a long-term treatment.

The dose of lactulose for chronic idiopathic constipation is adjusted according to the severity and desired effect, from a mild stool softener to diarrhea.

The dose is reduced in case of galactosemia since most of the preparations contain the monosaccharide galactose due to its synthesis process.

Lactulose can counteract the constipation effects of opioids and in the symptomatic treatment of hemorrhoids as a stool softener.


Lactulose helps treat ammonia in the blood, leading to hepatic encephalopathy. Lactulose helps trap ammonia (NH3) in the colon and binds to it.

It does this by using the intestinal flora to acidify the colon, transforming the free-diffusing ammonia into ammonium ions (NH + 4), which can no longer diffuse back into the blood.

It is also helpful in preventing hyperammonemia caused as a side effect of valproic acid administration.

Lactulose for hepatic encephalopathy generally requires relatively large oral doses three to four times a day, with episodic diarrhea and constant flatulence, almost a specific side effect.

People who take lactulose at this dose usually wear an adult diaper and plastic pants for any activities outside the home or at night (with a chux pad for the bed) because diarrhea can occur quickly and without much warning.

Small intestine bacterial overgrowth

Lactulose is used to test small intestine bacterial overgrowth (SIBO). Its reliability in diagnosing small intestinal bacterial overgrowth has been seriously questioned.

A large amount is administered with subsequent tests of molecular hydrogen gas in respiration.

The test is positive if there is an increase in exhaled hydrogen earlier than expected with normal colonocyte digestion.

It has been hypothesized that a previous result indicates that digestion occurs in the small intestine. An alternative explanation for the differences in outcomes is the variation in short bowel transit time between the subjects tested.

Special populations

No evidence of harm to the baby has been found when used during pregnancy. In general, it is considered safe while breastfeeding.

Mechanism of action

It is a disaccharide formed from a molecule, each of the simple sugars (monosaccharides) fructose and galactose.

Lactulose is not usually present in raw milk, but it is a product of heat processes:

The higher the heat, the greater the amount of this substance (from 3.5 mg / l in low-temperature pasteurized milk to 744 mg / l in packaged sterilized milk). It is produced commercially by isomerization of lactose.

Lactulose is not absorbed from the small intestine or broken down by human enzymes, so it remains in the digestive bolus for most of its course, causing water retention through osmosis, leading to more stool. Smooth and easy to pass.

It has a secondary laxative effect in the colon, where it is fermented by the intestinal flora, producing metabolites that have osmotic powers and stimulating effects of peristalsis (such as acetate), but also methane associated with flatulence.

How can I take Duphalac if I am constipated?

Duphalac is an effective medicine to treat chronic constipation. It is also used to prevent the effect of liver failure on the brain by removing certain toxic chemicals from the blood.

A single dose of lactulose should be swallowed in a single dose and should not be kept in the mouth for an extended period. The dosage should be adjusted according to the individual needs of the patient.

Duphalac syrup is a clear liquid to be swallowed. Swallow the medicine quickly. Could you not keep it in your mouth?

Using a measure of medicine will ensure that you receive the correct dose. Duphalac can be taken diluted or undiluted.

Duphalac oral powder can be taken from a spoon or put directly on the tongue and then washed off with a drink of water or liquid. Duphalac (lactulose) powder must be mixed with at least 4 ounces of water.

The crystals can also be sprinkled on food or mixed with water or liquids before swallowing; disperse the powder through the liquid while stirring.

Dosage in constipation or when loose stools are considered beneficial to health: Lactulose can be administered in a single daily dose or two divided doses using the measuring cup.

Chronic constipation

The usual starting dose for constipation in adults is 15 to 45 ml per day, and the maintenance dose is 15 to 30 ml per day. It may take 1-2 days for Duphalac to work fully.

Duphalac should be given to infants and children under medical supervision. The usual doses are:

Pediatric: Very little information has been recorded on the use of lactulose in young children and adolescents. As with adults, the personal goal in proper treatment is to produce 2 or 3 loose stools per day.

Based on available information, the recommended starting daily oral dose for infants is 2.5 to 10 ml in divided doses. The total daily amount is 40 ml to 90 ml for older children and adolescents.

If the initial dose causes diarrhea, the amount should be reduced immediately. If diarrhea persists, lactulose should be discontinued. Another serious pediatric dosage recommendation:

Babies under one year :

Initial dose (first three days): 5 ml daily.

Children from 1 to 6 years old :

Initial dose (first three days): 5 to 10 ml daily.

Children 7-14 years :

Initial dose (first 3 days): 15 ml daily.

Adult: The usual oral dose for adults is 2 to 3 tablespoons (30 ml to 45 ml, containing 20 grams to 30 grams of lactulose) three or four times a day. The dose can be adjusted every day or two to produce 2 or 3 loose stools a day.

Hourly doses of 30 ml to 45 ml of lactulose solution can be used to induce the rapid laxation indicated in the initial phase of therapy for portal-systemic encephalopathy.

When the laxative effect has been achieved, the dose of lactulose can be reduced to the recommended daily dose. The improvement in the patient’s condition can occur within 24 hours but cannot begin earlier than 48 hours or even later.

Long-term continuous therapy is indicated to decrease the severity and prevent the recurrence of portal-systemic encephalopathy. The dose of lactulose for this purpose is the same as the recommended daily dose.

After a few days, the starting dose can be adjusted to the maintenance dose based on response to treatment. It may take several days (2-3 days) of treatment before the effect of the treatment occurs.

Rectal dosage

When the adult patient is in the imminent coma of portal-systemic encephalopathy and aspiration hazard exists, or when necessary endoscopic or intubation procedures physically interfere with the administration of recommended oral doses.

Duphalac can be given as a retention enema through a rectal balloon catheter. Cleansing enemas containing soap suds or other alkaline agents should not be used.

Three hundred ml of lactulose solution should be mixed with 700 ml of water or physiological saline and kept for 30 to 60 minutes.

The lactulose enema can be repeated every 4 to 6 hours. If this lactulose enema is inadvertently passed too soon, it can be repeated immediately.

Duphalac is best taken each day simultaneously, preferably at breakfast time. Long-term use of laxatives is undesirable. Keep taking Duphalac for as long as your doctor or pharmacist tells you.

As a general rule, constipation patients should drink plenty of water and increase the amount of fiber in their diet. If you do not understand the instructions, ask your doctor or pharmacist for help.

If you have trouble remembering to take your medicine, ask your pharmacist for some advice.

Before taking Duphalac

When you shouldn’t take it

But that’s what Duphalac is:

  • You are allergic to lactulose, galactose, lactose, or other sugar.
  • You have galactosemia.
  • You have a disaccharidase deficiency.
  • You are on a low-galactose or galactose-free diet.
  • You are on a lactose-free diet.
  • You have a bowel obstruction (obstruction other than normal constipation).

Do not take Duphalac after the expiry date printed on the label or if the seal on the cap is broken.

Before you start taking it

Tell your doctor or pharmacist if you have allergies to:

  • Any other medication.
  • Any other substance, such as food, preservatives, or colorants.

Tell your doctor or pharmacist if you have or have ever had any medical conditions, especially the following:

  • Painful abdominal symptoms with no identifiable cause.
  • Diabetes.
  • Lactose intolerance.

Tell your doctor or pharmacist if you are breastfeeding or plan to breastfeed. Your doctor or pharmacist will discuss the possible risks and benefits of using Duphalac while breastfeeding.

Duphalac has no or minor influence on the ability to drive and use machines. If you have not told your doctor or pharmacist about any of the above, tell them before you start taking Duphalac.

While you are taking Duphalac

Things you should do

Tell any other doctor, dentist, pharmacist, or healthcare professional, such as naturopaths who are treating you, that you are taking Duphalac.

If you are about to start any new medicine, tell your doctor, dentist, pharmacist, or other healthcare professional that you are taking Duphalac.

If you need to have a colonoscopy or proctoscopy, tell your doctor that you are taking Duphalac.

Things you should not do

Do not take Duphalac to treat any other complaint unless your doctor or pharmacist tells you to.

Side effects of Duphalac

During the first few days of taking Duphalac, you may feel bloated due to increased wind and intestinal cramps. These effects are usually mild and disappear after a few days.

In high doses, you can suffer from diarrhea. If this happens, reduce the amount and inform your doctor or pharmacist.

Tell your doctor or pharmacist if you notice any of the following and they worry you:

Gas, bloating, belching, stomach noises/buzzing, nausea, and cramps may occur.

Tell your doctor right away if any of these unlikely but severe side effects occur:

  • Diarrhea, vomiting, muscle weakness/cramps, irregular heartbeat, mental/mood changes, seizures, severe or persistent stomach / abdominal pain, bloody stools, and rectal bleeding.

These side effects are rare. Very rarely, babies who receive Duphalac can develop dehydration.

Some of these side effects (for example, potassium levels in the blood) can only be found when your doctor orders blood tests.

Contact your doctor or pharmacist if you notice other effects not listed above.

After using duphalac

Keep Duphalac in a cool place where the temperature stays below 25 ° C. Do not store Duphalac in the refrigerator or freezer.

If your doctor or pharmacist tells you to stop taking Duphalac or that the liquid has passed the expiration date ask your pharmacist what to do with any leftover medicine.

The liquid form of Duphalac may take on a slightly darker color, but this is a harmless effect. However, do not use the medicine if it becomes very dark or if it is thicker or thinner in texture.

If you use Duphalac for an extended period, your doctor may want you to have occasional blood tests. Do not miss any scheduled appointments.

During pregnancy, this medicine should only be used when needed. Discuss the risks and benefits with your doctor. Do not use this medicine without telling your doctor if you are breastfeeding a baby.

Duphalac precautions

There may be drugs that interact with Duphalac. Tell your doctor about all your prescription and over-the-counter medicines, vitamins, minerals, herbal products, and drugs prescribed by other doctors.

Don’t start a new medicine without checking with your doctor.

Older people may be at increased risk of losing blood minerals (e.g., potassium, sodium) when using this drug, especially if they are using it for a long time.

Do not start, stop, or change the dose of any medicine before checking with your doctor or pharmacist first.

In the general management of portal-systemic encephalopathy, it must be recognized that there is underlying severe liver disease with complications such as electrolyte disturbances (e.g., hypokalemia), for which other specific therapy may be necessary.

Babies given lactulose can develop hyponatremia and dehydration.

Interactions with other drugs

There have been conflicting reports on the concomitant use of neomycin and lactulose solution.

Theoretically, eliminating certain colonic bacteria by neomycin and possibly other anti-infective agents can interfere with the desired degradation of lactulose and thus prevent acidification of colonic contents.

Therefore, the condition of the lactulose-treated patient should be closely monitored in the case of concomitant oral anti-infective therapy.

Other laxatives should not be used, especially during the initial phase of therapy for portal-systemic encephalopathy, because loose stools resulting from their use may falsely suggest that the proper dose of lactulose has been reached.

Duphalac overdose

Overdose symptoms may include diarrhea, stomach pain, hot and dry skin, confusion, uneven heartbeat, extreme thirst, increased urination, discomfort in the legs, muscle weakness, or a limp feeling.


Diarrhea is an indication of an overdose. Severe diarrhea can cause hypovolaemia, hypokalaemia, and hypernatremia, especially in elderly or seriously ill patients. If diarrhea develops, the dose should be reduced.

Intestinal cystoid pneumatosis can occur with lactulose therapy (the active ingredient in Duphalac) due to increased intracolonic pressure caused by ammonia sequestration in the intestine, mainly when there is an accompanying violation of the integrity of the intestinal mucosa.

Gastrointestinal side effects have included abdominal cramps, gas bloating, flatulence, belching, intestinal bloating, cramps, nausea and vomiting, and with excessive doses, diarrhea.

Colonic dilation has been reported in elderly patients. Rare cases of intestinal cystic pneumatosis have been reported.


Metabolic side effects have included hypernatremia, hypokalemia, and hyperchloremic metabolic acidosis. An isolated case of severe and intractable lactic acidosis has been reported.

Fluid and electrolyte disturbances, including severe hypokalemia, hypernatremia, and hyperchloremic metabolic acidosis, usually result from severe diarrhea and subsequent fluid loss.

A case of lactulose-induced lactic acidosis has also been reported in diarrhea. Elderly and seriously ill patients may be at increased risk of adverse metabolic effects with lactulose.

Importance of diet

Laxatives should be used for short-term relief only unless otherwise directed by a physician.

An adequate diet that contains forage (whole-grain bread and cereals, bran, fruits, and green leafy vegetables), with 6 to 8 full glasses (8 ounces each) of fluids per day, and daily exercise is more important to maintain a functional, healthy gut.

Also, for people who have problems with constipation, foods such as cakes, desserts, sugar, sweets, cakes, and cheese can make constipation worse.

Ensure your healthcare professional knows if you are on a special diet, such as low sodium or low sugar diet. Some laxatives contain large amounts of sodium or sugars.