CYP2D6 inhibitors, such as SSRI medications, may increase plasma levels of risperidone and those medications. Since risperidone can cause hypotension, its use should be monitored closely when a patient is also taking antihypertensive medicines to avoid severe low blood pressure. Risperidone and its metabolite paliperidone are reduced in efficacy by P-glycoprotein inducers such as St Johns wort

Discontinuation
The British National Formulary recommends a gradual withdrawal when discontinuing antipsychotic treatment to avoid acute withdrawal syndrome or rapid relapse. Some have argued the additional somatic and psychiatric symptoms associated with dopaminergic super-sensitivity, including dyskinesia and acute psychosis, are common features of withdrawal in individuals treated with neuroleptics. This has led some to suggest the withdrawal process might itself be schizomimetic, producing schizophrenia-like symptoms even in previously healthy patients, indicating a possible pharmacological origin of mental illness in a yet unknown percentage of patients currently and previously treated with antipsychotics. This question is unresolved, and remains a highly controversial issue among professionals in the medical and mental health communities, as well as the public. Dementia
Older people with dementia-related psychosis are at a higher risk of death. Pharmacology
Pharmacodynamics
Risperidone has been classified as a "qualitatively atypical" antipsychotic agent with a relatively low incidence of extrapyramidal side effects (when given at low doses) that has more pronounced serotonin antagonism than dopamine antagonism. Risperidone contains the functional groups of benzisoxazole and piperidine as part of its molecular structure. Although not a butyrophenone, it was developed with the structures of benperidol and ketanserin as a basis. It has actions at several 5-HT (serotonin) receptor subtypes.
Other uses
Risperidone has shown promise in treating therapy-resistant obsessive-compulsive disorder, when serotonin reuptake inhibitors alone are not sufficient.Risperidone has proven to be effective in treatment with Attention deficit hyperactivity disorder especially in cases of aggression or with another mental condition.Risperidone has not demonstrated a benefit in the treatment of eating disorders or personality disorders, except for limited evidence in schizotypal personality disorder. Forms
Available forms of risperidone include tablet, oral dissolving tablet, oral solution, and powder and solvent for suspension for injection. Adverse effects
Common side effects include movement problems, sleepiness, dizziness, trouble seeing, constipation, and increased weight. About 9 to 20% of people gained more than 7% of the baseline weight depending on the dose. Serious side effects may include the potentially permanent movement disorder tardive dyskinesia, as well as neuroleptic malignant syndrome, an increased risk of suicide, and high blood sugar levels. In older people with psychosis as a result of dementia, it may increase the risk of death.While atypical antipsychotics appear to have a lower rate of movement problems as compared to typical antipsychotics, risperidone has a high risk of movement problems among the atypicals. Atypical antipsychotics, however, are associated with a greater amount of weight gain and other metabolic side effects. Drug interactions
Carbamazepine and other enzyme inducers may reduce plasma levels of risperidone. If a person is taking both carbamazepine and risperidone, the dose of risperidone will likely need to be increased. The new dose should not be more than twice the patients original dose.