Comparative Pharmacology
Head-to-head clinical analysis: DUPHALAC versus GENERLAC.
Peer-Reviewed Evidence
Head-to-head clinical analysis: DUPHALAC versus GENERLAC.
DUPHALAC vs GENERLAC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Duphalac (lactulose) is a synthetic disaccharide that is not absorbed in the gastrointestinal tract. It is metabolized by colonic bacteria to short-chain fatty acids (e.g., acetic, lactic, formic acids), which lower colonic pH. This acidic environment favors the conversion of ammonia (NH3) to ammonium (NH4+), which is trapped in the colon and excreted in feces, thereby reducing systemic ammonia absorption. Additionally, the osmotic effect of lactulose and its metabolites draws water into the colon, producing a laxative effect.
Lactulose is a synthetic disaccharide that is not absorbed in the small intestine. It is metabolized by colonic bacteria to short-chain fatty acids (e.g., lactic, acetic, and formic acids), which osmotically increase intraluminal water content, soften stool, and stimulate peristalsis. In hepatic encephalopathy, the acidic environment reduces intestinal ammonia production and absorption by promoting conversion of NH3 to NH4+.
Oral: 15-30 mL once daily, may increase to 30-45 mL twice daily if needed. Rectal (enema): 150-300 mL as a single dose.
10-45 mL orally once daily, adjusted to produce 2-3 soft stools per day. Maximum 60 mL/day.
None Documented
None Documented
Not applicable; systemic exposure is negligible. Orally administered lactulose acts locally in the colon.
Not applicable; lactulose is a non-absorbable disaccharide that exerts a local osmotic effect in the colon without systemic absorption. Systemic half-life is not relevant as it does not enter circulation.
Lactulose is not absorbed from the gastrointestinal tract; it is excreted unchanged in feces (>99%).
Primarily fecal (≥90%) as unchanged drug via colonic excretion; renal elimination is negligible (<1%).
Category C
Category C
Osmotic Laxative
Osmotic Laxative