Lactulose Fresenius Kabi Austria (Lactulose)

Lactulose acts on the gastrointestinal tract to manage conditions related to bowel motility and ammonia accumulation.

• Constipation: softens stool and promotes bowel movements, helping relieve occasional or chronic constipation.
• Hepatic encephalopathy: lowers blood ammonia levels, improving mental status in patients with liver disease.
• Prophylaxis of hepatic encephalopathy: used to prevent recurrence of encephalopathic episodes in chronic liver disease patients.

• Lactulose is a synthetic disaccharide that is not absorbed in the small intestine. In the colon, bacterial enzymes hydrolyze it to acidic metabolites, increasing osmotic pressure and drawing water into the lumen, which softens stool and stimulates peristalsis. The resulting acidification traps ammonia as ammonium, reducing its absorption and lowering systemic ammonia concentrations, which benefits hepatic encephalopathy management.

Lactulose may cause a range of adverse reactions, most of which are related to its laxative action.

Common Side Effects

• Abdominal bloating: sensation of fullness or swelling in the abdomen.
• Flatulence: increased intestinal gas production.
• Diarrhea: loose, watery stools occurring after dosing.
• Nausea: feeling of sickness or urge to vomit.
• Abdominal cramps: painful muscle contractions in the gut.
• Thirst: increased desire for fluids.

Serious or Rare Side Effects

• Severe electrolyte imbalance: abnormal levels of sodium, potassium, or other electrolytes.
• Dehydration: excessive loss of body water leading to dizziness or low blood pressure.
• Allergic reaction: rash, itching, swelling, or difficulty breathing.
• Severe abdominal pain: intense, persistent pain requiring medical evaluation.

Before initiating lactulose therapy, consider the following safety measures.

• Renal function assessment: evaluate kidney status, especially in patients with chronic kidney disease.
• Electrolyte monitoring: check serum electrolytes periodically during prolonged use.
• Diabetes caution: monitor blood glucose as lactulose may affect carbohydrate metabolism.
• Intestinal obstruction avoidance: do not use in patients with known bowel blockage.
• Hepatic impairment dose adjustment: consider lower doses in severe liver disease.
• Store at room temperature: keep in the original container, protect from moisture and direct sunlight.

Lactulose can interact with other medicines, altering their effectiveness or safety.

Major Interactions (Avoid)

• Antacids containing magnesium: may reduce lactulose efficacy by neutralizing acidity.
• Oral diuretics: increased risk of electrolyte disturbances when combined with lactulose‑induced fluid loss.
• Insulin or oral hypoglycemics: lactulose may affect glucose levels, requiring dose adjustments.

Moderate Interactions (Monitor Closely)

• Probiotics: concurrent use may modify gut flora and influence lactulose metabolism.
• Other laxatives: combined use can lead to excessive bowel activity and dehydration.