Second-Generation Antipsychotic Pregnancy: Avoid in pregnancy unless clearly necessary

Risperidone

Brand names: Risperdal

Adult dose

Dose: 0.5-2 mg twice daily (BPSD); 4-8 mg/day (schizophrenia)

Route: Oral

Frequency: Twice daily

Max: 2 mg/day for BPSD in elderly; 16 mg/day for schizophrenia

Only antipsychotic with a specific UK licence for short-term treatment of persistent aggression in Alzheimer's dementia — licensed for up to 6 weeks only

Paediatric dose

Dose: Seek specialist opinion N/A/kg

Route: Oral

Frequency: Seek specialist opinion

Max: Seek specialist opinion

Seek specialist opinion

Dose adjustments

Renal

Start at 0.5 mg twice daily; titrate cautiously in renal impairment

Hepatic

Start at 0.5 mg twice daily; titrate cautiously

Paediatric weight-based calculator

Patient weight (kg)

Seek specialist opinion

Clinical pearls

MHRA 2004: Only risperidone is licensed for BPSD in the UK — maximum 6 weeks, lowest effective dose, after non-pharmacological interventions have failed
Cerebrovascular risk: approximately doubles stroke risk in elderly with dementia — document consent and review regularly
Lewy body dementia: risperidone is contraindicated — neuroleptic sensitivity can cause severe irreversible Parkinsonism or sudden death
NICE NG97 (Dementia): antipsychotics for BPSD only after risk-benefit discussion; review at 6 weeks and discontinue if no clear benefit
Before prescribing: rule out Lewy body dementia (fluctuating cognition, visual hallucinations, Parkinsonism)

Contraindications

Dementia with Lewy bodies (severe sensitivity — can be fatal)
Parkinson's disease dementia (relative — risk of neuroleptic sensitivity)

Side effects

Stroke (cerebrovascular events — doubled risk in elderly with dementia)
Postural hypotension and falls
Extrapyramidal symptoms (dose-related)
Sedation
QT prolongation
Metabolic effects (less than olanzapine)
Hyperprolactinaemia

Interactions

CNS depressants (additive)
QT-prolonging drugs (additive)
Antihypertensives (enhanced hypotensive effect)
CYP2D6 inhibitors — fluoxetine, paroxetine (increase risperidone levels)

Monitoring

Neurological symptoms (EPSE)
Blood pressure (postural)
Cognitive function
Cerebrovascular events
Weight and metabolic parameters
Regular review and attempt to discontinue at 6 weeks

Reference: BNFc; BNF 90; MHRA Drug Safety Update 2004 (risperidone BPSD); NICE NG97 (Dementia); AGS Beers Criteria 2023. Verify against your local formulary and the latest BNF before prescribing.

Curated clinical cross-links plus same-class fallbacks.

Calculators

Drugs

Olanzapine · Second-Generation Antipsychotic

Pathways