How does lactulose work?
Lactulose draws water into the bowel, softening stools and making them easier to pass. It also helps reduce ammonia levels in people with liver disease by encouraging the removal of toxins through the bowel.
What is lactulose used to treat?
Lactulose is commonly prescribed for:
- Constipation (to soften stools and improve bowel movements)
- Hepatic encephalopathy (a liver-related brain condition caused by high ammonia levels)
Who can take lactulose?
Lactulose is suitable for most adults and children, including pregnant women and older adults, as it is generally gentle and safe.
Who might not be able to take lactulose?
Lactulose may not be suitable if you:
- Have galactose intolerance or lactose intolerance
- Have a blockage in the bowel (intestinal obstruction)
- Are on a low-galactose diet
- Have diabetes (as lactulose contains sugars that can affect blood sugar levels)
Can I take lactulose if I’m pregnant or breastfeeding?
Yes, lactulose is safe to take during pregnancy and while breastfeeding. However, always consult your doctor before taking it.
What if I miss a dose?
If you forget a dose, take it as soon as you remember. If it’s close to your next dose, skip the missed one—do not take two doses at once.
How effective is lactulose?
Lactulose is effective at relieving constipation and managing ammonia levels in liver disease when taken as directed. It may take 24 to 48 hours to have an effect.
What should I do if I take too much?
Taking too much lactulose can cause severe diarrhoea, bloating, and stomach pain. If symptoms are severe, seek medical advice.
What dose of lactulose is usually taken?
- For constipation: 15ml to 30ml daily, adjusted as needed
- For hepatic encephalopathy: 30ml to 50ml three times daily
Your doctor will determine the right dose based on your condition.
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What are the side effects of lactulose?
Common side effects include:
- Bloating or wind (flatulence)
- Mild stomach cramps
- Diarrhoea (if taken in high doses)
Serious side effects, such as severe diarrhoea or electrolyte imbalances, require medical attention.
How should I take lactulose?
Lactulose is taken as a liquid, usually once or twice daily. It can be taken with water, juice, or food to improve the taste.
When should lactulose be taken?
Lactulose is usually taken at the same time each day, often in the morning or evening.
What are the brand names for lactulose?
Lactulose is available as a generic medicine, but some branded versions include:
- Duphalac
- Lactugal
Final thoughts
Lactulose is a gentle and effective treatment for constipation and liver disease. To get the best results, take it as prescribed, stay hydrated, and speak to your doctor if symptoms persist or worsen.
