Comparative Pharmacology
Head-to-head clinical analysis: FLUOXETINE POSTPARTUM SAFETY versus PAXIL CR.
Peer-Reviewed Evidence
Head-to-head clinical analysis: FLUOXETINE POSTPARTUM SAFETY versus PAXIL CR.
Fluoxetine-Safety-Postpartum 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 in the synaptic cleft, potentiating serotonergic activity in the CNS.
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.
20 mg orally once daily, initially; may increase after several weeks to a maximum of 80 mg/day. Administer in the morning.
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
Fluoxetine: 4-6 days (acute), 4-6 weeks (chronic); norfluoxetine: 4-16 days. Steady-state achieved after 2-4 weeks.
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.
Renal (80% as metabolites, 10% as unchanged drug) and fecal (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 A/B
Category C
SSRI Antidepressant
SSRI Antidepressant