Paliperidone is sold under the brand name "Invega".
Invega is an atypical antipsychotic that is one of the active metabolites of risperidone. It is FDA approved for the acute and maintenance treatment of Schizophrenia in adults.
Each of the atypical antipsychotics has its own profile or personality. Paliperidone is quite new to the market, but it is expected to be more similar to risperidone than different. That suggests that the liability to weight gain is intermediate compared to other atypical antipsychotics. It can be expected to cause initial agitation or akathisia in some patients. Like risperidone, it may also cause hyperprolactinemia (the hormone that causes women to lactate and stop having periods after they have a baby) in a substantial proportion of the patients who take it.
Paliperidone has complex mechanisms of action that include blockade of dopamine and serotonin receptors for its therapeutic benefits. Blockade of histamine and acetylcholine receptors account for most of its adverse effects. The atypical antipsychotics as a group are distinguished by blockade of postsynaptic serotonin 2A receptors which confers relative protection against many of the serious adverse effects (e.g. tardive dyskinesia, akathisia and dystonic reactions) of the first generation, or typical, antipsychotics (e.g. haloperidal (Haldol), perphenizine (Trilafon), chlorpromazine (Thorazine), and others).
Paliperidone is metabolized to several inactive metabolites via the liver. The half life of paliperidone is about one day and consequently if stopped abruptly (not recommended) it is out of the body in about 5 days.
Possible adverse effects can include diabetes, increased levels of prolactin, weight gain, abnormal triglycerides and cholesterol, insulin resistance, increased Qtc intervals, sedation, dizziness, dry mouth, constipation, and others. There is data that suggest this category of medication can rarely cause strokes in the elderly.
Paliperidone, along with the other atypical antipsychotics, carries a warning from the FDA against the possibility of new onset diabetes mellitus. Guidelines for the appropriate medical monitoring of this category of medications for these possible medical adverse events were published in 2003. We follow these guidelines at Scott P. Hoopes, M.D., & Associates. It you are prescribed paliperidone you will be referred to our Metabolic Clinic for medical monitoring. Following these guidelines is essential for the responsible use of all the atypical antipsychotics in patients of all ages.
Paliperidone has no effects on liver enzyme systems and consequently does not significantly effect the elimination of other medications.
If you miss a dose of paliperidone do not add it to your next dose. It is important to take risperidone regularly as prescribed.
