Comparative Pharmacology
Head-to-head clinical analysis: QUETIAPINE versus RISPERDAL CONSTA.
Peer-Reviewed Evidence
Head-to-head clinical analysis: QUETIAPINE versus RISPERDAL CONSTA.
Quetiapine vs RISPERDAL CONSTA
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Antagonist at serotonin 5-HT2A, dopamine D2, histamine H1, and adrenergic α1 receptors; weak partial agonist at 5-HT1A and serotonin transporter.
Risperidone is an atypical antipsychotic with high affinity for serotonin 5-HT2A and dopamine D2 receptors. It also binds to alpha1-adrenergic, alpha2-adrenergic, and histamine H1 receptors, with low affinity for muscarinic receptors. The combination of 5-HT2A and D2 antagonism is thought to improve negative symptoms and reduce extrapyramidal side effects.
Initial: 25 mg PO BID, titrate to effective range 150-750 mg/day divided BID-TID; schizophrenia: 150-750 mg/day, bipolar disorder: 400-800 mg/day, major depressive disorder (adjunct): 150-300 mg/day at bedtime.
25 mg intramuscular every 2 weeks; may increase to 37.5 mg or 50 mg after 4 weeks if needed.
None Documented
None Documented
Clinical Note
moderateQuetiapine + Levofloxacin
"Quetiapine may increase the QTc-prolonging activities of Levofloxacin."
Clinical Note
moderateQuetiapine + Norfloxacin
"Quetiapine may increase the QTc-prolonging activities of Norfloxacin."
Clinical Note
moderateQuetiapine + Gemifloxacin
"Quetiapine may increase the QTc-prolonging activities of Gemifloxacin."
Clinical Note
moderateQuetiapine + Fluticasone propionate
"The risk or severity of adverse effects can be increased when Quetiapine is combined with Fluticasone propionate."
Terminal elimination half-life: ~6-7 hours (parent drug); extended-release: ~7 hours. Clinically, dosing is twice daily for immediate-release; once daily for extended-release.
The terminal elimination half-life of risperidone is approximately 20 hours for CYP2D6 extensive metabolizers and 24 hours for poor metabolizers (accounting for both risperidone and 9-hydroxyrisperidone). The half-life of the active moiety is about 20 hours, allowing for biweekly dosing of the long-acting injection.
Renal: 73% (as metabolites), Fecal: 20% (as metabolites), unchanged drug: <1% renal
Risperidone and its active metabolite 9-hydroxyrisperidone are primarily excreted renally (70%), with 14% excreted in feces. The remainder is eliminated via biliary and metabolic pathways.
Category C
Category C
Atypical Antipsychotic
Atypical Antipsychotic