Lactulose
Indications
Lactulose is used for:
Constipation, Hepatic encephalopathy
Adult Dose
Constipation
Solution: 15-30 mL (10-20 g) PO once daily; may be increased to 60 mL (40 g) once daily
Portal Systemic Encephalopathy
Prophylaxis
30-45 mL (20-30 g) PO q6-8hr, adjusted until 2-3 soft stools/day; if acute, may be given q1-2hr until 2-3 soft stools/day
Treatment
20-30 g (30-45 mL) PO q1hr to induce rapid defecation; reduced to 20-30 g q6-8hr after defecation achieved; titrated to produce 2-3 soft stools/day
Child Dose
Constipation
0.7-2 g/kg/day (1-3 mL/kg/day) PO in divided doses; not to exceed 40 g/day (60 mL/day)
Portal Systemic Encephalopathy
Prophylaxis
Infants: 2.5-10 mL/day (1.7-6.67 g/day) PO in divided doses; titrated to produce 2-3 soft stools/day
Children and adolescents: 40-90 mL/day (26.7-60 g/day) PO in divided doses; titrated to produce 2-3 soft stools/day
Renal Dose
Administration
Contra Indications
Lactulose is contraindicated in patients with galactosaemia and intestinal obstruction.
Precautions
It should be used with caution in patients with lactose intolerance and diabetes.
Lactation: Unknown whether drug is distributed into milk; use with caution
Pregnancy-Lactation
Pregnancy category: B
Lactation: Unknown whether drug is distributed into milk; use with caution
Interactions
May prevent release of mesalazine in the colon. Decreased effect with oral neomycin, antacids.
Side Effects
Side effects of Lactulose :
Initial dosing may produce flatulence and intestinal cramps, which are usually transient. Excessive dosage can lead to diarrhoea, dehydration, nusea, vomiting, hypokalemia.
Mode of Action
Lactulose promotes peristalsis by producing an osmotic effect in the colon with resultant distention. In hepatic encephalopathy, it reduces absorption of ammonium ions and toxic nitrogenous compounds, resulting in reduced blood ammonia concentrations.