Risperidone


Generic Medicine Info
Indications and Dosage
Intramuscular
Schizophrenia
Adult: Give oral risperidone for a few days to assess tolerability prior to initiating. Patients not stabilised on oral risperidone: 25 mg every 2 wk. Patients stabilised on oral risperidone for at least 2 wk in doses ≤4 mg daily: 25 mg every 2 wk. Patients stabilised on oral risperidone for at least 2 wk in doses >4 mg daily: 37.5 mg every 2 wk. Continue oral risperidone for the 1st 3 wk after the 1st inj.
Elderly: No dosage adjustment needed.

Oral
Schizophrenia
Adult: Initially, 2 mg daily, may increase to 4 mg on the 2nd day, adjust further if needed. Doses may be given in 1-2 divided doses. Maintenance: 4-6 mg daily. Max: 16 mg daily.
Elderly: Initially, 0.5 mg bid gradually increased in increments of 0.5 mg bid to 1-2 mg bid.

Oral
Acute manic episodes of bipolar disorder
Adult: Initially, 2 mg once daily. May increase in increments of 1 mg daily at intervals of at least 24 hr. Max: 6 mg daily.
Elderly: Initially, 0.5 mg bid gradually increased in increments of 0.5 mg bid to 1-2 mg bid.

Oral
Moderate dementia in Alzheimer's disease, Severe dementia in Alzheimer's disease
Adult: Initially, 0.25 mg bid. Adjust in increments of 0.25 mg bid on alternate days. Usual dose: 0.5 mg bid (up to 1 mg bid, if needed). Max duration: 6 wk.

Oral
Conduct disorder
Child: 5-18 yr ≥50 kg: Initially, 0.5 mg once daily. Adjust in increments of 0.5 mg once daily on alternate days. Usual dose: 1 mg once daily; some may require up to 1.5 mg once daily. <50 kg: Initially, 0.25 mg once daily. Adjust in increments of 0.25 mg once daily on alternate days. Usual dose: 0.5 mg once daily; some may require up to 0.75 mg once daily.
Renal Impairment
Oral
Half the initial and subsequent doses. Dose titration should be slower.

Intramuscular
Initially, 0.5 mg bid oral risperidone during the 1st wk, increased to 1 mg bid or 2 mg once daily during the 2nd wk. If total oral daily dose of at least 2 mg is well tolerated, an IM dose of 25 mg can be given every 2 wk. Continue oral supplementation for 3 wk after 1st inj until the main release from the inj site has begun.
Hepatic Impairment
Oral
Half the initial and subsequent doses. Dose titration should be slower.

Intramuscular
Initially, 0.5 mg bid oral risperidone during the 1st wk, increased to 1 mg bid or 2 mg once daily during the 2nd wk. If total oral daily dose of at least 2 mg is well tolerated, an IM dose of 25 mg can be given every 2 wk. Continue oral supplementation for 3 wk after 1st inj until the main release from the inj site has begun.
Administration
May be taken with or without food.
Special Precautions
Patient w/ known CV disease (e.g. history of MI or ischaemia, heart failure, conduction abnormalities), cerebrovascular disease, conditions that would predispose to hypotension (e.g. dehydration, hypovolemia), parkinsonian syndrome or dementia w/ Lewy bodies, history of seizures or other conditions that may potentially lower seizure threshold, pre-existing hyperprolactinaemia, possible prolactin-dependent tumours. Avoid abrupt withdrawal. Hepatic or renal impairment. Elderly w/ dementia-related psychosis. Pregnancy and lactation.
Adverse Reactions
Agitation, insomnia, anxiety, headache, sedation, extrapyramidal effects; dyspepsia, nausea and vomiting, abdominal pain, constipation, blurred vision, sexual dysfunction including priapism, urinary incontinence, rash and other allergic reactions, drowsiness, concentration difficulties, dizziness, fatigue, rhinitis; tachycardia, wt gain, oedema, increased liver enzyme values, dose-dependent increases in prolactin levels, intra-operative floppy iris syndrome. Rarely, hyperglycaemia and exacerbation of pre-existing DM, leucopenia, neutropenia, thrombocytopenia, seizures, body temp dysregulation, hyponatraemia and tardive dyskinesia.
Potentially Fatal: Neuroleptic malignant syndrome, cerebrovascular events (e.g. stroke, transient ischemic attack), agranulocytosis.
Patient Counseling Information
This drug may affect performance of skilled tasks e.g. driving and operating machinery.
MonitoringParameters
Monitor blood glucose in patients w/ or at risk of developing diabetes. Monitor wt regularly.
Overdosage
Symptoms: Drowsiness, sedation, tachycardia, hypotension, extrapyramidal symptoms, QT prolongation, convulsions. Management: Establish and maintain clear airway, ensure adequate oxygenation and ventilation. Gastric lavage and admin of activated charcoal w/ laxative should be considered when intake was less than 1 hr before. Treat hypotension and circulatory collapse w/ IV fluids and/or sympathomimetic agents. Admin an anticholinergic agent in case of severe extrapyramidal symptoms.
Drug Interactions
May enhance effects of antihypertensives and CNS depressants. Increased risk of QT prolongation when given w/ drugs known to cause this effect (e.g. antiarrhythmics, TCAs). May antagonise the actions of levodopa and other dopamine agonists. Carbamazepine and other enzyme inducers (e.g. rifampicin, phenobarbital) may decrease the serum levels of the active antipsychotic fraction of risperidone. Increased plasma concentration w/ fluoxetine, paroxetine or verapamil.
Food Interaction
May enhance CNS depressant effect of alcohol.
Action
Description: Risperidone is a benzisoxazole atypical antipsychotic w/ mixed serotonin dopamine antagonist activity that binds to 5-HT2-receptors in the CNS and in the periphery w/ a very high affinity; binds to dopamine-D2 receptors w/ less affinity.
Pharmacokinetics:
Absorption: Readily absorbed from the GI tract. Time to peak plasma concentration: W/in 1-2 hr.
Distribution: Distributed into breast milk. Volume of distribution: 1-2 L/kg. Plasma protein binding: Approx 90% (risperidone), 77% (9-hydroxyrisperidone).
Metabolism: Extensively hepatic via hydroxylation mediated by CYP2D6 isoenzyme to 9-hydroxyrisperidone (main active metabolite); oxidative N-dealkylation is a minor metabolic pathway.
Excretion: Via urine (70%) and to a lesser extent in the faeces (14%). Elimination half-life: 20 hr (oral); 3-6 days (IM).
Chemical Structure

Chemical Structure Image
Risperidone

Source: National Center for Biotechnology Information. PubChem Database. Risperidone, CID=5073, https://pubchem.ncbi.nlm.nih.gov/compound/Risperidone (accessed on Jan. 23, 2020)

Storage
Tab/oral soln: Store between 15-25°C. Protect from light and moisture. Inj: Store between 2-8°C. Protect from light.
MIMS Class
ATC Classification
N05AX08 - risperidone ; Belongs to the class of other antipsychotics.
References
Anon. Risperidone. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 11/12/2014.

Buckingham R (ed). Risperidone. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 15/12/2014.

Joint Formulary Committee. Risperidone. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 15/12/2014.

McEvoy GK, Snow EK, Miller J et al (eds). Risperidone. AHFS Drug Information (AHFS DI) [online]. American Society of Health-System Pharmacists (ASHP). https://www.medicinescomplete.com. Accessed 15/12/2014.

Disclaimer: This information is independently developed by MIMS based on Risperidone from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2021 MIMS. All rights reserved. Powered by MIMS.com
  • Dyperidone
  • Ridonex
  • Rispedin-1/Rispedin-2/Rispedin-4
  • Risperdal
  • Rispolux
  • Sizodon 1/Sizodon 2/Sizodon 4
  • Steviso
Register or sign in to continue
Asia's one-stop resource for medical news, clinical reference and education
Sign up for free
Already a member? Sign in