Risperidone

SGA / Benzisoxazole·Psychiatry - Antipsychotics

Schizophrenia, Bipolar mania, Behavioral and Psychological Symptoms of Dementia (BPSD), Autism irritability

Authority requiredPBSSGARisperdal, Risperdal Consta (LAI)4 mg tablet+2

Max Dose

8 mg/day

Half-life

20 h

Prolactin

HIGH RISK

EPS Risk

DOSE-DEP

Rapid Summary

Overview

Potent D2 and 5-HT2A antagonist. At low doses, it acts like a modern SGA. At high doses (>4mg), it acts like an older typical antipsychotic, causing severe EPS.

Maximum Dose

Max 8 mg/day (Doses > 6 mg carry severe EPS risks with minimal extra benefit).

Clinical Focus

The most notorious SGA for causing hyperprolactinemia (galactorrhea, gynecomastia, amenorrhea).

Bottom Line

Risperidone is a potent D2/5-HT2A antagonist effective for psychosis and behavioural disturbance, but causes dose-dependent hyperprolactinaemia and extrapyramidal symptoms more than other atypicals.

Formulation & Access

Brand Names

Risperdal, Risperdal Consta (LAI)

Oral Routes

Tablets (0.5 to 4 mg), ODT Wafers, Oral Liquid (1 mg/mL).

Parenteral

Long-Acting Injection (LAI) for IM use.

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Schizophrenia, Bipolar mania, Behavioral and Psychological Symptoms of Dementia (BPSD), Autism irritability.

Clinical Place

Highly effective for acute positive symptoms. Only SGA officially approved for BPSD in Australia.

Quick reference

Class & Role

SGA / Benzisoxazole — Potent D2 and 5-HT2A antagonist.

Route / Formulation

Tablets (0.5 to 4 mg), ODT Wafers, Oral Liquid (1 mg/mL). (Risperdal, Risperdal Consta (LAI))

Usual Dose & Max

PO 1 mg BD initially. Titrate to target 4-6 mg/day. Max 8 mg/day (Doses > 6 mg carry severe EPS risks with minimal extra benefit).

Key Indication Doses

Schizophrenia / Bipolar: PO 1 mg BD initially. Titrate to target 4-6 mg/day. BPSD (Dementia Agitation): PO 0.25 - 0.5 mg BD. Max 2 mg/day in elderly/BPSD. Short-term use only. Renal Impairment: Halve the starting dose if eGFR < 30.

Best Uses

Risperidone is a potent D2/5-HT2A antagonist effective for psychosis and behavioural disturbance, but causes dose-dependent hyperprolactinaemia and extrapyramidal symptoms more than other atypicals.

Avoid / Cautions

Known hypersensitivity. Severe CNS depression.

Key Risks

Endocrine: Hyperprolactinemia (causes milk production, loss of periods, sexual dysfunction, and long-term osteoporosis). Neurological: Extrapyramidal side effects (EPS) including parkinsonism and akathisia, strongly dose-dependent > 4 mg/day. Metabolic: Weight gain, metabolic syndrome.

Key Interactions

CYP2D6 inhibitors (Fluoxetine, Paroxetine, Bupropion) massively increase risperidone levels, triggering severe EPS and hyperprolactinemia. Antihypertensives (additive hypotension).

Monitoring

Serum Prolactin if symptoms develop. Baseline BSL, Lipids, and Weight. Monitor for rigidity, tremor, or severe restlessness (akathisia).

Clinical Pearl

Risperidone bridges the gap between old and new antipsychotics. If you prescribe 6-8 mg of Risperidone, you are essentially prescribing Haloperidol. The patient will almost certainly require Benzatropine to counteract the severe stiffness.

Access

Authority requiredRisperdal, Risperdal Consta (LAI)4 mg tablet

Brand: Risperdal, Risperdal Consta (LAI)
PBS status: Authority required
Formulation: Tablets (0

Risperidone

SGA / Benzisoxazole·Psychiatry - Antipsychotics

Schizophrenia, Bipolar mania, Behavioral and Psychological Symptoms of Dementia (BPSD), Autism irritability

Authority requiredPBSSGARisperdal, Risperdal Consta (LAI)4 mg tablet+2

Max Dose

8 mg/day

Half-life

20 h

Prolactin

HIGH RISK

EPS Risk

DOSE-DEP

Rapid Summary

Overview

Potent D2 and 5-HT2A antagonist. At low doses, it acts like a modern SGA. At high doses (>4mg), it acts like an older typical antipsychotic, causing severe EPS.

Maximum Dose

Max 8 mg/day (Doses > 6 mg carry severe EPS risks with minimal extra benefit).

Clinical Focus

The most notorious SGA for causing hyperprolactinemia (galactorrhea, gynecomastia, amenorrhea).

Bottom Line

Risperidone is a potent D2/5-HT2A antagonist effective for psychosis and behavioural disturbance, but causes dose-dependent hyperprolactinaemia and extrapyramidal symptoms more than other atypicals.

Formulation & Access

Brand Names

Risperdal, Risperdal Consta (LAI)

Oral Routes

Tablets (0.5 to 4 mg), ODT Wafers, Oral Liquid (1 mg/mL).

Parenteral

Long-Acting Injection (LAI) for IM use.

Prescribing & PBS

Authority Required (PBS).

Indications & Use

Primary

PBSTGA

Schizophrenia, Bipolar mania, Behavioral and Psychological Symptoms of Dementia (BPSD), Autism irritability.

Clinical Place

Highly effective for acute positive symptoms. Only SGA officially approved for BPSD in Australia.

Quick reference

Class & Role

SGA / Benzisoxazole — Potent D2 and 5-HT2A antagonist.

Route / Formulation

Tablets (0.5 to 4 mg), ODT Wafers, Oral Liquid (1 mg/mL). (Risperdal, Risperdal Consta (LAI))

Usual Dose & Max

PO 1 mg BD initially. Titrate to target 4-6 mg/day. Max 8 mg/day (Doses > 6 mg carry severe EPS risks with minimal extra benefit).

Key Indication Doses

Best Uses

Risperidone is a potent D2/5-HT2A antagonist effective for psychosis and behavioural disturbance, but causes dose-dependent hyperprolactinaemia and extrapyramidal symptoms more than other atypicals.

Avoid / Cautions

Known hypersensitivity. Severe CNS depression.

Key Risks

Key Interactions

CYP2D6 inhibitors (Fluoxetine, Paroxetine, Bupropion) massively increase risperidone levels, triggering severe EPS and hyperprolactinemia. Antihypertensives (additive hypotension).

Monitoring

Serum Prolactin if symptoms develop. Baseline BSL, Lipids, and Weight. Monitor for rigidity, tremor, or severe restlessness (akathisia).

Clinical Pearl

Access

Authority requiredRisperdal, Risperdal Consta (LAI)4 mg tablet

Brand: Risperdal, Risperdal Consta (LAI)
PBS status: Authority required
Formulation: Tablets (0