Comparative Pharmacology
Head-to-head clinical analysis: QUETIAPINE FUMARATE versus ZYPREXA RELPREVV.
Peer-Reviewed Evidence
Head-to-head clinical analysis: QUETIAPINE FUMARATE versus ZYPREXA RELPREVV.
QUETIAPINE FUMARATE vs ZYPREXA RELPREVV
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antagonist at serotonin 5-HT2A, dopamine D2, histamine H1, alpha1-adrenergic, and muscarinic M1 receptors. Also partial agonist at serotonin 5-HT1A and dopamine D2 receptors (depending on dose).
Olanzapine pamoate is a second-generation antipsychotic that antagonizes dopamine D2 and serotonin 5-HT2A receptors. It also binds to adrenergic α1, histamine H1, and muscarinic M1 receptors.
Immediate release: 25-100 mg orally twice daily, titrated as needed up to 400-800 mg/day divided twice daily. Extended release: 50-200 mg orally once daily, titrated up to 400-800 mg/day once daily.
210 mg intramuscular injection every 2 weeks; range 150-300 mg; max 300 mg per dose. For olanzapine-naive patients, establish tolerability with oral olanzapine before initiation.
None Documented
None Documented
Terminal elimination half-life is approximately 6-7 hours (quetiapine) and 9-12 hours for the active metabolite norquetiapine; with extended-release formulation, effective half-life is ~7 hours due to slower absorption. Clinical steady-state achieved within 2 days.
The terminal elimination half-life ranges from 30 to 60 days (mean ~45 days) after intramuscular injection, consistent with extended release from the depot formulation.
Renal: 73% (20% unchanged, remainder as metabolites); Fecal: 21%; Approximately 5% excreted in feces as unchanged drug.
Approximately 57% of the dose is excreted in urine (30% as unchanged drug, 27% as metabolites) and 30% in feces (primarily as metabolites).
Category A/B
Category C
Atypical Antipsychotic
Atypical Antipsychotic