Comparative Pharmacology
Head-to-head clinical analysis: CELONTIN versus MYSOLINE.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CELONTIN versus MYSOLINE.
CELONTIN vs MYSOLINE
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.
Primidone is a barbiturate anticonvulsant that acts by enhancing GABA-A receptor activity and possibly by blocking sodium channels.
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.
250 mg orally 3 times daily; may increase by 250 mg/day every 3 days; usual maintenance 250 mg 3-4 times daily; maximum daily dose 1500 mg.
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.
Primidone: 5-15 hours (mean 10 hours); PEMA: 10-18 hours; Phenobarbital: 50-120 hours. Steady state achieved in 2-4 weeks due to accumulation of phenobarbital.
Renal: approximately 40-60% as unchanged drug; hepatic metabolism accounts for the remainder, with metabolites excreted renally.
Primidone is excreted primarily in urine; approximately 60-80% as unchanged drug and metabolites (PEMA, phenobarbital), with less than 10% in feces.
Category C
Category C
Anticonvulsant
Anticonvulsant