Comparative Pharmacology
Head-to-head clinical analysis: PAXIL versus PROZAC.
Head-to-head clinical analysis: PAXIL versus PROZAC.
PAXIL vs PROZAC
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Paroxetine is a selective serotonin reuptake inhibitor (SSRI) that potentiates serotonergic activity in the central nervous system by inhibiting the reuptake of serotonin (5-HT) from the synaptic cleft, leading to increased serotonin levels.
Selective serotonin reuptake inhibitor (SSRI); potentiates serotonergic activity in the CNS by blocking the reuptake of serotonin into presynaptic neurons.
20 mg orally once daily, typically in the morning; may be increased in 10 mg/day increments at intervals of at least 1 week to a maximum of 50 mg/day.
20 mg orally once daily, initially; may increase to 40 mg once daily after several weeks; maximum 80 mg once daily.
None Documented
None Documented
Mean terminal half-life 21 hours (range 3–65 hours); steady-state achieved within 7–14 days; nonlinear kinetics with dose increase leading to disproportionate increases in half-life due to saturable hepatic metabolism (CYP2D6).
Fluoxetine: 4-6 days; norfluoxetine: 4-16 days; extensive accumulation with chronic dosing, steady-state in 4-5 weeks
Renal: 64% (2% unchanged, 62% as metabolites); Fecal: 36% via bile; urinary excretion of unchanged paroxetine <2%.
Renal: ~80% (primarily as metabolites, <10% unchanged); fecal: ~15%
Category C
Category C
SSRI Antidepressant
SSRI Antidepressant