Risperidone Overview and Indications

Study Notes

Risperidone (brand name Risperdal) is classified as an antipsychotic and falls under the benzisoxazoles category.
It is classified as Category C for pregnancy and is available in oral (PO) and intramuscular (IM) forms.
The liver metabolizes Risperidone.

Notable side effects include Neuroleptic Malignant Syndrome (NMS), dizziness, aggression, and various extrapyramidal symptoms (EPS).
Other effects: headache, altered sleep patterns (increased duration, insomnia, sedation), nervousness, and fatigue.
Gastrointestinal reactions include constipation, diarrhea, dry mouth, nausea, and abdominal pain.
May cause weight changes (gain/loss), increased thirst (polydipsia), and sexual/reproductive issues (decreased libido, dysmenorrhea).
Cardiac effects may consist of arrhythmias and orthostatic hypotension.

Geriatric patients may require a lower dosage due to a higher risk of cerebrovascular events.
Not indicated for patients with dementia-related psychosis.
Safety in pediatric patients has not been established.
Regular monitoring of body mass index (BMI), blood glucose (A1C), cholesterol, complete blood count (CBC), liver function tests (LFT), and eye examinations is essential.
Increased attention is needed for signs of EPS, tardive dyskinesia (TD), and suicidality.

The mechanism of action is believed to involve the antagonism of dopamine and serotonin in the central nervous system (CNS).

Use with caution in clients who are debilitated, have hepatic or renal impairment, cardiovascular disease, or a history of seizures.
Patients with a history of drug abuse or suicide attempts should also be closely monitored.
Individuals with diabetes may experience worsened glucose control.

May reduce the effectiveness of antiparkinsonian medications like levodopa.
Co-administration with enzyme inducers such as carbamazepine or phenytoin can reduce Risperidone's effectiveness.
Fluoxetine and paroxetine may enhance the effectiveness of Risperidone.
Clozapine may lower Risperidone metabolism and elevate its effects.
Central nervous system depressants (e.g., kava, valerian, chamomile) can increase sedation effects.