Comparative Pharmacology
Head-to-head clinical analysis: LEXAPRO versus PAXIL CR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: LEXAPRO versus PAXIL CR.
LEXAPRO vs PAXIL CR
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Selective serotonin reuptake inhibitor (SSRI); inhibits serotonin reuptake at the presynaptic neuron, potentiating serotonergic activity.
Paroxetine is a selective serotonin reuptake inhibitor (SSRI). It potentiates serotonergic activity in the CNS by inhibiting the reuptake of serotonin at the presynaptic neuronal membrane, resulting in increased serotonin concentrations in the synaptic cleft.
10 mg orally once daily; may increase to 20 mg once daily after at least 1 week.
12.5-37.5 mg orally once daily in the morning; initial dose 12.5 mg/day, titrate by 12.5 mg/day at intervals of at least 1 week to maximum 50 mg/day.
None Documented
None Documented
27-32 hours (mean ~30 h); steady state reached in ~1 week; linear kinetics at therapeutic doses.
The terminal elimination half-life of paroxetine (PAXIL CR) is approximately 15-20 hours. This supports once-daily dosing and requires about 5-7 days to reach steady-state concentration.
Primarily renal (approx. 80% as metabolites, 8% as unchanged drug); biliary/fecal elimination accounts for ~15%.
Renal excretion accounts for approximately 64% of the administered dose, with 2% as unchanged parent drug and the remainder as metabolites. Fecal excretion accounts for about 36%, mostly as metabolites. Less than 1% is excreted in bile.
Category C
Category C
SSRI Antidepressant
SSRI Antidepressant