Lactulose
Lactulose is a synthetic combination of two naturally-occurring sugars, glucose and galactose. It is used as a laxative to treat constipation and to reduce hepatic encephalopathy. The mechanism of action of lactulose is not fully understood, but it appears to either displace toxins or increase stool water content or both. Lactulose can take up to 72 hours to take effect.
Absorption and Route of Elimination
Absorption of lactulose is incomplete, so most of it passes through the intestine without being absorbed. It is fermented by bacteria in the digestive tract absorbs some of it. The remainder, usually discharged in the stools, is metabolized by bacteria in the large intestine to lactic and acetic acids. These metabolites are rapidly absorbed and metabolized by the body.
Dosage and Administration
The recommended dosage of lactulose is 15-45ml per day (15mL for children under 2 years of age). It should be taken in three or four divided doses with 1-2 hours between doses, and on an empty stomach. Lactulose can be taken with water, fruit juice, or milk.
Side Effects, Toxicity, and Precaution
The most common side effects of lactulose are stomach cramping, bloating, and diarrhea. It can also cause electrolyte disturbances, vitamin deficiencies, and dehydration. Lactulose should be used with caution in patients with hepatic encephalopathy, as it may increase the level of ammonia in the blood. It should not be used in patients with severe electrolyte disturbance, malabsorption, or certain severe gastrointestinal diseases. It should also be used with caution in pregnant and lactating women.
Interaction
Lactulose may interact with some medications, including laxatives, antibiotics, antacids, and other drugs that decrease peristalsis. It should also not be taken with oral vitamins and minerals, as it may decrease their absorption.
Disease Interactions
Lactulose may worsen symptoms of some diseases, including renal impairment, intestinal obstruction, colitis, and Crohn's disease. It should also not be used in patients with diabetic ketoacidosis.
Drug Interactions
Lactulose may reduce the absorption of some medications, including antibiotics, oral vitamin and mineral supplements, and antacids. It may also interfere with the effect of certain drugs, such as lithium and some cancer medications.
Food Interactions
Lactulose may interact with some foods, including dairy products, and foods containing sorbitol. It is recommended to avoid these foods when taking lactulose.
Pregnancy and Lactation Use
Lactulose is generally considered safe for pregnant and lactating women. However, it is recommended to consult with a healthcare professional before taking this medication during pregnancy or lactation.
Acute Overdose
An acute overdose of lactulose may lead to watery stools, electrolyte imbalance, abdominal pain, and nausea or vomiting. It is recommended to seek medical help if a person experiences any of these symptoms.
Contraindication
Lactulose is contraindicated in patients with known hypersensitivity to it or any other components of its formulation, as well as in patients with severe electrolyte disturbances, malabsorption, and certain gastrointestinal diseases.
Use Direction
Lactulose should be taken as directed by a healthcare professional. Generally, it is recommended to take 15-45ml (15mL for children under 2 years of age) with 1-2 hours between doses, on an empty stomach.
Storage Conditions
The drug should be stored in tightly closed containers in room temperature away from heat and moisture.
Volume of Distribution
Lactulose is not highly lipophilic and thus not expected to distribute into the central nervous system. The volume of distribution is up to 10-20 L/kg.
Half Life
The elimination half-life is approximately 6.2 hours.
Clearance
The clearance of lactulose is about 0.1 L/hr/kg.
See in details version Lactulose also Lactulose in bangla
Some Frequently Asked Questions About Lactulose
1. What is lactulose?
Lactulose is a synthetic sugar used as a laxative to treat constipation and as a treatment for hepatic encephalopathy, a liver-related brain condition. It is not absorbed by the body but works in the colon.
2. How does lactulose work?
Lactulose draws water into the intestines, softening stool and promoting bowel movements. It also lowers ammonia levels in the blood by converting ammonia into a form that can be excreted.
3. What is lactulose used for?
It is primarily used to:
4. Is lactulose a prescription drug?
Yes, lactulose is typically available by prescription, though some formulations may be available over-the-counter in certain regions.
5. Who can take lactulose?
It is suitable for adults and children, including infants, under medical supervision, but it should be avoided by those with certain conditions like galactosemia.
6. How is lactulose taken?
It is taken orally as a liquid (syrup) or sometimes in powder form mixed with water or juice.
7. What is the typical dosage for constipation?
For adults, the usual starting dose is 15-30 mL (1-2 tablespoons) daily, adjusted based on response. Children’s doses vary by age and weight.
8. What is the dosage for hepatic encephalopathy?
For adults, it’s typically 30-45 mL taken 3-4 times daily, adjusted to produce 2-3 soft stools per day.
9. How long does lactulose take to work for constipation?
It usually takes 24-48 hours to produce a bowel movement.
10. Can lactulose be taken daily?
Yes, it can be taken daily for chronic constipation or hepatic encephalopathy as prescribed by a doctor.
11. Does lactulose cause dependency?
No, lactulose is not habit-forming and does not cause physical dependence like some stimulant laxatives.
12. Can lactulose be taken with food?
Yes, it can be taken with or without food, though mixing it with juice or water may improve taste.
13. What does lactulose taste like?
It has a sweet, syrupy taste that some find unpleasant. Mixing it with juice can help mask the flavor.
14. Is lactulose safe during pregnancy?
It is generally considered safe during pregnancy (Category B), but consult a doctor before use.
15. Can breastfeeding mothers take lactulose?
Yes, it is safe for breastfeeding mothers as it is not absorbed into the bloodstream or excreted in breast milk in significant amounts.
16. What are the side effects of lactulose?
Common side effects include:
17. Can lactulose cause diarrhea?
Yes, taking too much can lead to diarrhea. Dosage should be adjusted to avoid this.
18. Does lactulose interact with other medications?
It has minimal interactions since it isn’t absorbed, but it may reduce the effectiveness of oral medications taken at the same time by speeding their passage through the gut.
19. Can lactulose be used for weight loss?
No, lactulose is not intended or effective for weight loss.
20. Is lactulose safe for diabetics?
It contains small amounts of sugar, so diabetics should consult a doctor, though it rarely affects blood sugar significantly.
21. What happens if I miss a dose?
For constipation, take it when you remember. For hepatic encephalopathy, follow your doctor’s advice, but don’t double the dose.
22. Can I overdose on lactulose?
Overdose is unlikely but can cause severe diarrhea, dehydration, and electrolyte imbalances. Seek medical help if this occurs.
23. How should lactulose be stored?
Store it at room temperature, away from heat, moisture, and direct light. Do not freeze.
24. Does lactulose expire?
Yes, check the expiration date on the bottle. Expired lactulose may be less effective.
25. Can children take lactulose?
Yes, it’s safe for children when prescribed by a doctor, with doses adjusted for age and weight.
26. Is lactulose a natural product?
No, it is a synthetic disaccharide made from lactose (milk sugar).
27. Can lactulose treat IBS?
It may help with constipation in irritable bowel syndrome (IBS-C), but it’s not a cure for IBS itself.
28. Why does lactulose reduce ammonia levels?
It acidifies the colon, trapping ammonia as ammonium ions, which are then excreted in stool.
29. Can lactulose cause gas?
Yes, gas and bloating are common as bacteria in the colon ferment the lactulose.
30. Is lactulose gluten-free?
Yes, lactulose is naturally gluten-free.
31. Can lactulose be used long-term?
Yes, it can be used long-term under medical supervision, especially for chronic conditions like hepatic encephalopathy.
32. What should I do if lactulose doesn’t work?
Consult your doctor; they may adjust the dose or suggest an alternative treatment.
33. Can lactulose be given to elderly patients?
Yes, it’s commonly used in the elderly for constipation, but monitor for dehydration or electrolyte issues.
34. Does lactulose need refrigeration?
No, it should be stored at room temperature, not refrigerated.
35. Can lactulose treat hemorrhoids?
It doesn’t treat hemorrhoids directly but can prevent straining by softening stools, which may help.
36. Is lactulose the same as lactose?
No, lactulose is derived from lactose but is a different compound with laxative properties.
37. Can lactulose cause dehydration?
Excessive use leading to diarrhea can cause dehydration, so proper dosing is key.
38. What if I’m allergic to lactulose?
Allergic reactions are rare, but if you experience rash, swelling, or difficulty breathing, stop use and seek medical help.
39. Can lactulose be mixed with alcohol?
It’s not recommended to mix lactulose with alcoholic beverages, though moderate alcohol use doesn’t typically interact with it.
40. Does lactulose help with liver disease?
Yes, it’s used to manage hepatic encephalopathy, a complication of liver disease, by reducing ammonia levels.
41. Can lactulose be taken at bedtime?
Yes, it can be taken at bedtime for constipation, though timing may vary for hepatic encephalopathy treatment.
42. Is lactulose available in tablet form?
No, it’s typically available as a syrup or powder, not tablets.
43. Can lactulose cause stomach pain?
Yes, cramping or discomfort can occur, especially if the dose is too high.
44. Does lactulose affect gut bacteria?
Yes, it acts as a prebiotic, feeding beneficial gut bacteria, which helps produce its laxative effect.
45. Can lactulose be used after surgery?
Yes, it’s often used post-surgery to prevent constipation, but only under medical guidance.
46. Is lactulose safe for people with kidney disease?
Generally yes, but consult a doctor, especially if electrolyte imbalances are a concern.
47. Can lactulose turn stools green?
No, it doesn’t typically change stool color; green stools may have another cause.
48. What’s the difference between lactulose and other laxatives?
Unlike stimulant laxatives (e.g., senna), lactulose is an osmotic laxative, drawing water into the bowel rather than stimulating muscle contractions.
49. Can lactulose be used for detox?
It’s not a detox agent but helps remove ammonia in liver conditions, which might be considered a form of toxin clearance.
Prof. Dr. Md. Shahjamal Khan
Diabetes, Thyroid & Hormone Diseases Specialist
Endocrinology Doctor in Dhaka