Comparative Pharmacology
Head-to-head clinical analysis: CELEXA versus PROZAC WEEKLY.
Peer-Reviewed Evidence
Head-to-head clinical analysis: CELEXA versus PROZAC WEEKLY.
CELEXA vs PROZAC WEEKLY
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Selective serotonin reuptake inhibitor (SSRI); potentiates serotonergic activity in the CNS by blocking reuptake of serotonin into presynaptic neurons.
Selective serotonin reuptake inhibitor (SSRI); potentiates serotonergic activity by blocking reuptake of serotonin at the presynaptic neuronal membrane.
20 mg orally once daily initially, may increase to 40 mg once daily after at least 1 week; maximum 40 mg/day.
90 mg orally once weekly
None Documented
None Documented
Terminal elimination half-life is approximately 35 hours (range 23–45 h) in healthy adults. This long half-life allows once-daily dosing; steady state is reached in about 1 week. In elderly patients, half-life may extend to 45–90 hours.
Fluoxetine: 4-6 days after single dose, 4-6 days (extended to 7-9 days with chronic dosing due to autoinhibition of CYP2D6); norfluoxetine: 9-31 days. Steady state achieved after 2-4 weeks.
Primarily renal: 75% as metabolites (10% as parent citalopram, 65% as desmethylcitalopram, didesmethylcitalopram, and citalopram-N-oxide). Fecal excretion accounts for approximately 20% of the dose. Biliary excretion minimal.
Renal excretion of metabolites (primarily fluoxetine glucuronide and norfluoxetine glucuronide) accounts for approximately 80% of elimination; fecal excretion accounts for approximately 15%.
Category C
Category C
SSRI Antidepressant
SSRI Antidepressant