Lactulose
ENULOSE
What it isNon-absorbed disaccharide fermented to organic acids; constipation and hepatic encephalopathy.
Why this oneIn encephalopathy it traps ammonia as ammonium in the gut lumen, which no other laxative does.
What limits itBloating and cramping limit adherence. Titrate to two or three soft stools daily; over-treatment causes dehydration and hypernatremia.
FDA-approved for
- constipation
- portosystemic encephalopathy
Off-label
- hepatic encephalopathy prophylaxis after a first episode
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Constipation | adult | 15-30 mL (10-20 g) QD | 60 mL/day |
Renal Undefined
Hepatic Undefined
Instructions
- 24-48 hours may be required to produce a normal bowel movement
- May mix with fruit juice, water, or milk for acceptability
Contraindications
- Patients who require a low-galactose diet (contains galactose <1.6 g/15 mL)
Cautions
- Excessive dosage can cause diarrhea with fluid loss, hypokalemia, hypernatremia
Adverse reactions
- Flatulence and intestinal cramps (usually transient)
- Diarrhea with excessive dosage
- Nausea and vomiting
Pregnancy Pregnancy Category B; use during pregnancy only if clearly needed
Lactation Undefined
NO BOXED WARNINGS
Principal riskBloating and cramping
Cost, est. cash$5–$150/month
Generic entry1988
Classes and tags
Clinical profile
Legacy pregnancy categoryC
Defining liabilityDiarrhea, dehydration and electrolyte disturbance, especially with excessive or prolonged use.
Mechanism of action: Lactulose ballicule
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