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Compound

Lactulose

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Lactulose. Non-absorbable disaccharide for constipation and HE.

How it works. Osmotic laxative; converted to lactic acid in colon, traps ammonia.

What the research supports. 1 graded claims. Strongest: Treats constipation and hepatic encephalopathy (moderate).

How much to take. Typical dose: 15–30 mL daily.

Side effects and interactions. 1 medication interaction listed. No serious side effects listed at normal doses.

Stacking. Pairs well with Multi-strain probiotic, L-glutamine, Milk thistle (silymarin).

Common forms. Available as Capsule or softgel, Powder, Sublingual or buccal, Liposomal liquid.

Key studies. 8 studies cited. The strongest are listed with links to PubMed.

Community. Experiences from people who have tried Lactulose. Anecdotes are not medical advice.

Lactulose. Non-absorbable disaccharide for constipation and HE.

Molecular structureC12H22O11 · 342.30 g/mol

What it is

Non-absorbable disaccharide for constipation and HE.

Food sources

Endogenously produced or biosynthesized moleculeStandardized pharmaceutical- or food-grade supplementCombined with cofactors that improve absorption or activity

Goals

Liver Health

How it works

Osmotic laxative; converted to lactic acid in colon, traps ammonia.

Pathways

  • Osmotic laxative
  • converted to lactic acid in colon, traps ammonia

Effects

  • +Treats constipation and hepatic encephalopathy supports

What the research supports

Treats constipation and hepatic encephalopathymoderate

Strong: consistent results across large trials or meta-analyses. Moderate: several trials, mostly positive. Limited: small or mixed studies. Preclinical: animal or cell research only.

Typical dose
15–30 mL daily
TimingConsistent daily timing recommended; split larger doses if GI tolerance is a concern.
With foodWith a meal containing fat for fat-soluble compounds; otherwise either.
Best formMost evidence is based on the capsule or softgel form.
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Side effects & interactions

Common side effects

  • Bloating
  • Diarrhea

Medication interactions

Prescription medications (general)minor

Always disclose Lactulose use to your prescriber — additive, antagonistic, or pharmacokinetic interactions are possible.

Check any supplement–medication combination with your pharmacist before starting.

Combines with

Pairs well

Common forms

  • Capsule or softgel
  • Powder
  • Sublingual or buccal
  • Liposomal liquid

Key studies

8 studies cited in total.

PubMed: Lactulose — Treats constipation and hepatic encephalopathy ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Lactulose and "Treats constipation and hepatic encephalopathy". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Lactulose — randomized controlled trial ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Lactulose and "randomized controlled trial". Filter by RCT, meta-analysis, or year on the results page.

PubMed: Lactulose — meta-analysis ↗
Systematic review · PubMed (NLM) · 2026

Opens current human and preclinical literature matching Lactulose and "meta-analysis". Filter by RCT, meta-analysis, or year on the results page.

Discussion

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