Name: Lactulose (Constilac, Cephulac)
Class: Laxative (Osmotic Laxative)
Mechanism: Galactose-fructose disaccharide ® osmotic effect in small intest. In colon, Metabolism. by bacteria to lactic, formic, and acetic acids ® osmotic effect.
Absorption:
Dist.:
Metabolism.:
Excretion, t½:
Toxicity/S.E.s: Not for use in pts on low galactose diets. Antacids can block fecal acidification (® ¯ effect on portal-systemic encephalopathy). Neomycin interferes w/lactulose action.
Utility: 1° use = symptomatic treatment of portal-systemic encephalopathy assoc. w/chronic liver disease. Acidified feces ® NH4+ excretion. Routine purgation.
Special Features: May be preferred for elderly patients for routine purgation, but expensive.