Comparative Pharmacology
Head-to-head clinical analysis: CELONTIN versus PHENYTEX.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CELONTIN versus PHENYTEX.
CELONTIN vs PHENYTEX
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Increases levels of gamma-aminobutyric acid (GABA) in the central nervous system, possibly by inhibiting GABA transaminase or enhancing GABA release; also reduces calcium influx into neurons, stabilizing neuronal membranes.
Stabilizes neuronal membranes by promoting sodium efflux and inhibiting calcium influx, thereby reducing repetitive firing of action potentials. Also enhances GABA-mediated inhibition.
300 mg orally three times daily, increased by 300 mg every 3-4 days as tolerated; usual maintenance dose 900-2400 mg/day in divided doses.
300-400 mg/day orally in divided doses, typically 100 mg three times daily or 200 mg twice daily; loading dose 1 g orally divided into three doses (400 mg, 300 mg, 300 mg) at 2-hour intervals, or 10-15 mg/kg IV at a rate not exceeding 50 mg/min.
None Documented
None Documented
Terminal elimination half-life: 40-60 hours in adults, 30-45 hours in children; prolonged liver disease or renal impairment may increase half-life.
22 hours (range 7-42 hours; prolonged in hepatic impairment; clinical context: steady-state achieved in 5-7 days)
Renal: approximately 40-60% as unchanged drug; hepatic metabolism accounts for the remainder, with metabolites excreted renally.
Renal (hepatic metabolism to inactive metabolites; <5% excreted unchanged in urine; biliary/fecal excretion minimal)
Category C
Category C
Anticonvulsant
Anticonvulsant