risperidone

General information

• Class: Antipsychotic
• Common US brands: RISPERDAL
• Typical dose range: Schizophrenia (adults): start 1–2 mg/day; increase by 1–2 mg/day to 4–6 mg/day (doses >6 mg/day increase EPS).
• Long-acting injectable formulation available.
• Therapeutic drug monitoring not routinely recommended.
• Last reviewed: 2025-12-28

Dosing & forms

• Forms/strengths: Tablets: 0.25–4 mg; orally disintegrating tablets 0.5–4 mg.; Oral solution: 1 mg/mL.; Long-acting injectables: Risperdal Consta 25 mg IM every 2 weeks with 3-week oral overlap (range 12.5–50 mg); Perseris 90 mg or 120 mg subcutaneous monthly.
• Frequency: Renal/hepatic impairment: start 0.5 mg twice daily; titrate cautiously.
• Typical range: Schizophrenia (adults): start 1–2 mg/day; increase by 1–2 mg/day to 4–6 mg/day (doses >6 mg/day increase EPS).

Mechanism (brief)

Dopamine D2 and serotonin 5‑HT2A receptor antagonism; also alpha‑1 and H1 activity.

Metabolism & Half‑life

• Metabolism: CYP2D6
• Half‑life: Single-dose mean 3 h; Steady-state mean 21 h

Therapeutic Drug Monitoring (TDM)

Recommended: No

Long‑acting injectable (LAI)

Sources

• RISPERDAL (risperidone) prescribing information — DailyMed (2025)
• Assessing the metabolic impact of aripiprazole versus risperidone in the treatment of schizophrenia: a randomized double-blind controlled clinical trial — BMC Psychiatry (2025)
• AGNP TDM Consensus — Pharmacopsychiatry (2018)
• The American Psychiatric Association Practice Guideline for the Treatment of Patients With Schizophrenia — American Psychiatric Association (2020)
• Risperidone in the treatment of schizophrenia — American Journal of Psychiatry (1994)