Comparative Pharmacology
Head-to-head clinical analysis: RISPERDAL versus ZYPREXA RELPREVV.
Peer-Reviewed Evidence
Head-to-head clinical analysis: RISPERDAL versus ZYPREXA RELPREVV.
RISPERDAL vs ZYPREXA RELPREVV
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Risperidone is a benzisoxazole atypical antipsychotic that antagonizes dopamine D2 and serotonin 5-HT2A receptors. It also blocks alpha1-adrenergic, alpha2-adrenergic, and histamine H1 receptors.
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.
2-8 mg orally once daily or divided twice daily; maximum 16 mg/day
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
20 hours (parent drug), 23 hours (active metabolite 9-hydroxyrisperidone). Steady state reached in 5-6 days. Extended in elderly and hepatic/renal impairment.
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: 70% (30% as unchanged drug, 40% as metabolites), Fecal/Biliary: 14%
Approximately 57% of the dose is excreted in urine (30% as unchanged drug, 27% as metabolites) and 30% in feces (primarily as metabolites).
Category C
Category C
Atypical Antipsychotic
Atypical Antipsychotic