User:Lena08041993/PaliperidoneExample

Paliperidone (trade name Invega), also known as 9-hydroxyrisperidone, is a dopamine antagonist and 5-HT2A antagonist of the atypical antipsychotic class of medications. It is marketed by Janssen Pharmaceutica. Invega is an extended release formulation of paliperidone that uses the OROS extended release system to allow for once-daily dosing.

Paliperidone palmitate (trade name Invega Sustenna, named Xeplion in Europe and other countries) is a long-acting injectable formulation of paliperidone palmitoyl ester indicated for once-every 28 days injection after an initial titration period. Paliperidone is used to treat mania and at lower doses as maintenance for bipolar disorder. It is also indicated in the US by the FDA for schizophrenia and schizoaffective disorder.

On May 18, 2015, a new formulation of paliperidone palmitate was approved by the FDA under the brand name Invega Trinza. A similar 3 -monthly injection of prolonged release suspension was approved in 2016 by the European Medicines Agency originally under the brand name Paliperidone Janssen, later renamed to Trevicta.

Medical use
It is used for the treatment of schizophrenia and schizoaffective disorder. In a 2013 study in a comparison of 15 antipsychotic drugs in effectivity in treating schizophrenic symptoms, paliperidone was ranked fifth, demonstrating medium-strong effectivity. Less effective than clozapine, slightly less effective than olanzapine and risperidone, and slightly more effective than haloperidol, quetiapine, and aripiprazole.

Adverse effects
Sources:


 * Very Common (>10% incidence)
 * Headache
 * Tachycardia
 * Somnolence (causes less sedation than most atypical antipsychotics )
 * Insomnia
 * Hyperprolactinaemia (seems to cause comparable prolactin elevation to its parent drug, risperidone )


 * Common (1–10% incidence)
 * Cough
 * Extrapyramidal side effects (EPSE; e.g. dystonia, akathisia, muscle rigidity, parkinsonism. It appears to produce similar EPSE to risperidone, asenapine and ziprasidone and more EPSE than olanzapine, clozapine, aripiprazole, quetiapine, amisulpride and sertindole )
 * Orthostatic hypotension
 * Weight gain (tends to produce a moderate degree of weight gain, possibly related to its potent blockade of the 5-HT2C receptor)
 * QT interval prolongation (tends to produce less QT interval prolongation than most other atypical antipsychotics and approximately as much QT interval prolongation as aripiprazole and lurasidone )
 * Nasopharyngitis
 * Anxiety
 * Indigestion
 * Constipation

Deaths
In April 2014, it was reported that 21 Japanese people who had received shots of the long-acting injectable paliperidone to date had died.

Pharmacology
Paliperidone is the primary active metabolite of the older antipsychotic risperidone. While its specific mechanism of action is unknown, it is believed paliperidone and risperidone act via similar, if not identical, pathways.

Paliperidone has antagonist effect at α1 and α2 adrenergic receptors and at H1 histamine receptors. It does not bind to muscarinic acetylcholine receptors. In addition, it blocks dopamine and serotonin receptors.

Paliperidone has less affinity for D4 receptors than risperidone.

Food increases the absorption of Invega type ER OROS prolonged-release tablet. Food increased exposure of Paliperidone by up to 50-60%, however, half-life was not significantly affected. The effect was probably due to a delay in the transit of the ER OROS formulation in the upper part of the GI channel, resulting in increased absorption (uptake).

The half life is 24 hours.

History
Paliperidone (as Invega) was approved by the Food and Drug Administration (FDA) for the treatment of schizophrenia in 2006. Paliperidone was approved by the FDA for the treatment of schizoaffective disorder in 2009. The long-acting injectable form of paliperidone, marketed as Invega Sustenna in U.S. and Xeplion in Europe, was approved by the FDA on July 31, 2009.

It was initially approved in Europe in 2007 for schizophrenia, the extended release form and use for schizoaffective disorder were approved in Europe in 2010, and extension to use in adolescents older than 15 years old was approved in 2014.