Risperidone is sold under the brand name "Risperdal".
Risperidone is an atypical antipsychotic that is not related structurally to any of the other atypical antipsychotics. It is FDA approved for the acute and maintenance treatment of Schizophrenia and Bipolar Disorder. It is also approved for the treatment of aggression and agitation in Autism in children as young as 6 years old.
Each of the atypical antipsychotics has its own profile or personality. Risperidone seems to be intermediate in its liability to weight gain of the atypical antipsychotics. It is felt by many to be more likely to cause initial agitation and akathisia than most of the other atypical antipsychotics. It alone of the atypical antipsychotics reliably causes 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.
Risperidone 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).
Risperidone is processed for elimination from the body (“metabolized”) in the liver to active and inactive compounds that are in turn eliminated by the kidneys. The half life of risperidone is significantly less than one day and consequently if stopped abruptly (not recommended) it is out of the body in about 3 days.
Possible adverse effects can include diabetes, increased levels of prolactin, weight gain, abnormal triglycerides and cholesterol, insulin resistance, sedation, dizziness, dry mouth, constipation, and others. There is data that suggest this category of medication can rarely cause strokes in the elderly.
Risperidone, 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 risperidone 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.
Risperidone has no effects on liver enzyme systems and consequently does not significantly effect the elimination of other medications.
If you miss a dose of risperidone do not add it to your next dose. It is important to take risperidone regularly as prescribed.
