Second-generation (atypical) antipsychotic
Active metabolite of risperidone; antagonizes dopamine D₂ and serotonin 5-HT₂A receptors; moderate affinity for α₁-adrenergic and histamine H₁ receptors
Schizophrenia, schizoaffective disorder
Augmentation in bipolar disorder, psychosis in dementia, management of behavioral dysregulation
Oral extended-release tablets, long-acting injectable (Sustenna monthly, Trinza every 3 months)
Oral: 3 mg daily, titrated up to 6–12 mg daily as tolerated; Injectable: dosing per manufacturer protocol following oral stabilization
Oral 3–12 mg/day; injectable doses per standard intervals after stabilizatio
Primarily excreted unchanged renally; minimal hepatic metabolism; half-life approximately 23 hours (oral), extended with injectables
Extrapyramidal symptoms (EPS), insomnia, hyperprolactinemia, weight gain, metabolic changes including glucose dysregulation
Increased prolactin levels may cause galactorrhea, sexual dysfunction, or gynecomastia; potential QT prolongation
Regular assessment for EPS, prolactin levels if clinically indicated, metabolic monitoring (weight, lipids, glucose), and periodic ECG in high-risk patients
Increased mortality in elderly patients with dementia-related psychosis
Paliperidone’s long-acting injectable formulations are advantageous for patients with poor medication adherence, including those with intellectual disability or severe cognitive impairment. Monitor closely for EPS and prolactin-related side effects, especially in elderly patients and those with Parkinson’s disease.