Comparative Pharmacology
Head-to-head clinical analysis: CEPHULAC versus TRILYTE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CEPHULAC versus TRILYTE.
CEPHULAC vs TRILYTE
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Lactulose, a synthetic disaccharide, is not absorbed from the gastrointestinal tract. It is metabolized by colonic bacteria to form short-chain fatty acids (e.g., lactic, acetic, formic acids), which acidify the colonic contents. In hepatic encephalopathy, the acidic environment converts ammonia (NH3) to ammonium (NH4+), which is poorly absorbed and excreted in feces. Additionally, the osmotic effect of lactulose draws water into the colon, softening stools and increasing bowel movements.
TRILYTE (polyethylene glycol 3350, sodium sulfate, sodium chloride, potassium chloride, sodium ascorbate, ascorbic acid) is an osmotic laxative. The active components induce diarrhea by osmotically drawing water into the gastrointestinal lumen, thereby increasing stool volume and stimulating peristalsis. Sodium ascorbate and ascorbic acid enhance the osmotic effect.
30-45 mL (6.67-10 g lactulose) orally 3-4 times daily for constipation; for hepatic encephalopathy, 30-45 mL orally 3-4 times daily titrated to produce 2-3 soft stools per day, or 300 mL in 700 mL of water or saline as retention enema for 30-60 min every 4-6 hours.
Adults: 1 liter (L) orally every 10-15 minutes until 4 L total consumed; complete ingestion within 4 hours.
None Documented
None Documented
Terminal elimination half-life is 7-10 hours (renal impairment: prolonged); systemic absorption is minimal (<3%) after oral administration, so half-life reflects clearance of absorbed fraction.
Not applicable; non-absorbed, acts locally in GI tract
Primarily renal (20-30% as unchanged drug) and fecal (up to 70% as unmetabolized drug via biliary elimination; following gastric acid-mediated degradation, only 5-10% reaches urine as intact lactulose; hepatic metabolism is negligible).
Renal excretion of intact electrolyte ions; negligible drug excretion
Category C
Category C
Laxative
Laxative