Comparative Pharmacology
Head-to-head clinical analysis: CONSTILAC versus GO EVAC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CONSTILAC versus GO EVAC.
CONSTILAC vs GO-EVAC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Constilac (lactulose) is a synthetic disaccharide that is not absorbed in the small intestine. In the colon, it is metabolized by bacteria to short-chain fatty acids (e.g., lactic acid), which osmotically draw water into the bowel, producing a laxative effect. Additionally, in hepatic encephalopathy, the acidification of colonic contents traps ammonia (NH3) as ammonium (NH4+), reducing its absorption.
Promotes gastrointestinal motility by acting as a stimulant laxative, likely through direct irritation of the colonic mucosa and possibly via local effects on enteric neurons.
Oral, 15-45 mL (10-20 g lactulose) once daily, titrated to produce 2-3 soft stools daily; may be given as a single dose or divided twice daily. Onset of action 24-48 hours.
10 mg orally once daily, with or without food.
None Documented
None Documented
Not applicable due to negligible systemic absorption; lactulose acts locally in the colon.
4.5-6 hours in healthy volunteers; prolonged to 10-14 hours in elderly patients and those with moderate renal impairment (CrCl 30-50 mL/min).
Primarily fecal as unchanged drug (systemic absorption negligible). Renal excretion accounts for <2% of any absorbed fraction. Biliary excretion is minimal.
Primarily renal; approximately 60% eliminated unchanged in urine within 24 hours, with 20% as metabolites. Biliary/fecal excretion accounts for 15-20%, and the remainder is metabolized via glucuronidation.
Category C
Category C
Osmotic Laxative
Osmotic Laxative