Comparative Pharmacology
Head-to-head clinical analysis: QUETIAPINE FUMARATE versus RISPERDAL.
Peer-Reviewed Evidence
Head-to-head clinical analysis: QUETIAPINE FUMARATE versus RISPERDAL.
QUETIAPINE FUMARATE vs RISPERDAL
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).
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.
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.
2-8 mg orally once daily or divided twice daily; maximum 16 mg/day
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.
20 hours (parent drug), 23 hours (active metabolite 9-hydroxyrisperidone). Steady state reached in 5-6 days. Extended in elderly and hepatic/renal impairment.
Renal: 73% (20% unchanged, remainder as metabolites); Fecal: 21%; Approximately 5% excreted in feces as unchanged drug.
Renal: 70% (30% as unchanged drug, 40% as metabolites), Fecal/Biliary: 14%
Category A/B
Category C
Atypical Antipsychotic
Atypical Antipsychotic