In this section
Poisoning - Guidelines for initial management
For 24 hour advice, contact
Victorian Poisons Information Centre 131126
Risperidone is an atypical antipsychotic that is a selective monoaminergic (MOA) antagonist with a strong affinity for serotonin Type 2 (5-HT2) receptors and a slightly weaker affinity for dopamine Type 2 (D2) receptors.
Risperidone blocks dopamine receptor resulting in extrapyramidal symptoms, and alpha1-adrenergic effects are responsible for orthostatic hypotension. Its affinity, albeit low affinity, for histamine receptors contributes to anticholinergic effects.
Risperidone is metabolised to an active metabolite 9-hydroxyrisperidone (aka paliperidone). Symptoms generally develop within 1 to 2 hours and peak by 4 to 6 hours, but delays have been reported (presumably for patients who are slow metabolisers). Resolution of symptoms may take several days (slow metabolisers half-life of 9-HR is 30 hrs)
Any symptomatic patient
All patients with deliberate self-poisoning or significant accidental ingestion
Urgent assessment is required for all children who may have ingested the following:
Usually manifest within 4 hours
Mild to moderate toxicity:
Activated Charcoal has a very limited role in treatment and should not be used without consultation with a toxicologist.
3. Specific treatment
Admission should be considered for:
Patients with an intentional overdose should have a mental health review.
Consult Contact Victorian Poisons Information Centre 131126 for advice
Patient with significant CNS depression/seizures or any cardiovascular instability.
Patient requiring care beyond the comfort level of the current hospital
For emergency advice and paediatric or neonatal ICU transfers, call the Paediatric Infant Perinatal Emergency Retrieval (PIPER) Service: 1300 137 650.
Period of observation as above
Patients should be warned that extrapyramidal movements may occur up to 3 days later.
Prior to discharge, adolescents who present with deliberate ingestions need a risk assessment regarding the likelihood of further ingestions or other attempts to self-harm.
Assessment of other drug and alcohol use should also be undertaken.
If, after risk assessment, it is deemed safe to discharge a patient from hospital, but ongoing mental health or drug and alcohol needs are identified, the adolescent should be linked with appropriate services (see links below for services in the State of Victoria).
Poisoning prevention for children Parent information
Victorian Poisons Information Centre: 13 11 26
Mental Health Services
National Youth Mental Health Foundation
Local headspace centres
Child and Adolescent Mental Health Services
Local services alphabetically by suburb / city
Drug and alcohol services
Victoria's Youth Drug and Alcohol Advice Service
1800 458 685
Last Updated April 2019