Comparative Pharmacology
Head-to-head clinical analysis: INVEGA versus RISPERDAL.
Head-to-head clinical analysis: INVEGA versus RISPERDAL.
INVEGA vs RISPERDAL
Comparing the clinical profiles, pharmacokinetic behaviors, and safety indices of these two therapeutic agents.
Paliperidone is the major active metabolite of risperidone. It is a benzisoxazole derivative antipsychotic with high affinity for serotonin 5-HT2A and dopamine D2 receptors. It also acts as an antagonist at α1 and α2 adrenergic receptors and H1 histaminergic receptors. It has no affinity for muscarinic receptors.
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.
Oral: 6 mg once daily; may increase to 9 mg/day if needed. IM (extended-release): 234 mg on day 1, 156 mg on day 8, then 117 mg monthly; adjust within range 39-234 mg per month.
2-8 mg orally once daily or divided twice daily; maximum 16 mg/day
None Documented
None Documented
Terminal elimination half-life is approximately 23-29 hours for oral administration (paliperidone extended-release). Once-daily dosing achieves steady-state within 4-5 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.
Primarily renal: 59-80% of dose excreted unchanged in urine (as parent drug and metabolites). Fecal: ~20-30%. Biliary elimination is minimal.
Renal: 70% (30% as unchanged drug, 40% as metabolites), Fecal/Biliary: 14%
Category C
Category C
Atypical Antipsychotic
Atypical Antipsychotic