paliperidone
Invega (paliperidone) is an atypical antipsychotic used for schizophrenia and schizoaffective disorder. It blocks dopamine D2 and serotonin 5-HT2A receptors, calming overactive signaling in thought and mood circuits. It is the major active metabolite of risperidone and is formulated as a once-daily extended-release tablet.
This page is based on EMA and FDA prescribing information for paliperidone, cross-checked with DailyMed labeling and MedlinePlus; the mechanism is explained in plain language, and analogies are used only where they stay accurate.
How it works
Explains what the medicine does in the body, not dosing, side effects, or safety.
An analogy
In schizophrenia, certain brain circuits fire too loudly because of excess dopamine and serotonin signaling. Paliperidone acts like a volume knob, turning down the gain at dopamine and serotonin receivers so that thoughts become more organized and mood more stable — without completely silencing normal signaling.
In simple terms
Paliperidone is an atypical antipsychotic that works mainly by blocking two types of receivers in the brain: dopamine D2 receptors and serotonin 5-HT2A receptors. In schizophrenia and schizoaffective disorder, dopamine signaling becomes overactive in circuits that handle thoughts and perceptions, leading to hallucinations, delusions, and disorganized thinking. By blocking D2 receptors, paliperidone reduces that overactivity. At the same time, blocking 5-HT2A receptors helps balance mood and reduces certain side effects that older antipsychotics cause. Paliperidone is the main active breakdown product of risperidone, but it is processed differently by the body — it does not need extensive liver metabolism, which makes its levels more predictable from person to person.
In depth
Paliperidone (9-hydroxyrisperidone) is the major active metabolite of risperidone. It functions as a potent antagonist at dopamine D2 and serotonin 5-HT2A receptors, with a higher 5-HT2A-to-D2 binding ratio that characterizes atypical antipsychotics. It also antagonizes alpha-1 and alpha-2 adrenergic receptors and histamine H1 receptors (contributing to sedation and orthostatic effects), and has moderate affinity for 5-HT1A, 5-HT2C, and 5-HT7 receptors. Unlike risperidone, paliperidone is not extensively metabolized by CYP2D6; it is eliminated largely unchanged in urine and feces, reducing pharmacokinetic variability across CYP2D6 metabolizer phenotypes. The extended-release oral formulation uses an osmotic push-pull system (OROS) to deliver steady plasma levels over 24 hours.
See it in motion
A schematic animation of the mechanism — simplified for clarity, not drawn to scale.
How paliperidone, the active metabolite of risperidone, blocks D2 and 5-HT2A receptors
- Paliperidone (9-hydroxyrisperidone) is the major active metabolite of risperidone.
- It functions as a potent antagonist at dopamine D2 and serotonin 5-HT2A receptors, with a higher 5-HT2A-to-D2 binding ratio that characterizes atypical antipsychotics.
- Unlike risperidone, paliperidone is not extensively metabolized by CYP2D6; it is eliminated largely unchanged in urine and feces, reducing pharmacokinetic variability across CYP2D6 metabolizer phenotypes.
- The extended-release oral formulation uses an osmotic push-pull system (OROS) to deliver steady plasma levels over 24 hours.
Target: Dopamine D2 and serotonin 5-HT2A receptors
Overactivity of dopamine D2 signaling is linked to psychotic symptoms; serotonin 5-HT2A overstimulation contributes to mood and thought dysregulation. Paliperidone blocks both, restoring balance.
Approved uses
Approved uses differ by country and change over time. Always follow your local prescribing information.
Approved uses in European Union
EMA- Treatment of schizophrenia in adults and adolescents 15 years and older
- Treatment of schizoaffective disorder in adults
Approved uses in United States
FDA- Treatment of schizophrenia in adults and adolescents
- Treatment of schizoaffective disorder as monotherapy and as adjunct to mood stabilizers and/or antidepressants
Approved uses in United States
DailyMed- Treatment of schizophrenia
- Treatment of schizoaffective disorder as monotherapy and adjunct to mood stabilizers and/or antidepressant therapy
Approved uses in United States
MedlinePlus- Treatment of schizophrenia and schizoaffective disorder
Official sources
The statements on this page trace back to these records.
- Invega (paliperidone) — Summary of product characteristics and package leaflet, English version
European Medicines Agency
- U.S. Food and Drug Administration: paliperidone prescribing information
U.S. Food and Drug Administration
- DailyMed: paliperidone extended-release labeling
DailyMed, U.S. National Library of Medicine
- MedlinePlus: paliperidone
MedlinePlus, U.S. National Library of Medicine
This page explains how the medicine works — it isn’t the patient leaflet. For anything that applies to you, read the leaflet that came with your medicine or ask your pharmacist.
MedUnfold provides educational content and is not medical advice. Always follow your local prescribing information and healthcare professional.