ClinCalc Pro
Menu
Calculators Drugs Pathways AI Dx Donate Get the App
Atypical (Second-generation) Antipsychotic — Benzamide Pregnancy: Use only if clearly needed — insufficient data. Neonatal EPS risk. Prefer established alternatives in pregnancy.

Amisulpride

Brand names: Solian

Adult dose

Dose: Acute schizophrenia (positive symptoms): 400–800mg daily in 2 divided doses. Predominant negative symptoms: 50–300mg OD. Maximum: 1200mg daily.
Route: Oral
Frequency: Once or twice daily
Max: 1200mg daily
Selective D2/D3 receptor antagonist — no activity at serotonin, histamine, muscarinic, or adrenergic receptors. At low doses (50–300mg/day): preferentially blocks presynaptic D2/D3 autoreceptors, enhancing dopaminergic transmission — beneficial for negative symptoms. At high doses (400–1200mg): blocks postsynaptic D2/D3 — treats positive symptoms. Renally excreted — dose reduction required in renal impairment.

Paediatric dose

Route: Oral
Frequency: Once or twice daily
Max: Not applicable
Not licensed under 18 years. Seek specialist child and adolescent psychiatry opinion.

Dose adjustments

Renal

eGFR 30–60: halve the dose. eGFR 10–30: use one-third of normal dose. eGFR <10: avoid.

Hepatic

No dose adjustment required — not hepatically metabolised.

Clinical pearls

  • Unique dose-dependent mechanism: low-dose amisulpride (50–300mg) specifically targets negative symptoms (avolition, alogia, flat affect) — one of few antipsychotics with evidence for negative symptom improvement
  • Hyperprolactinaemia is prominent — check prolactin if galactorrhoea, amenorrhoea, sexual dysfunction, or bone loss develop
  • Renally excreted (unlike most antipsychotics) — dose reduction mandatory in renal impairment (unusual requirement for an antipsychotic)
  • QTc: baseline ECG and monitoring — higher risk than most atypical antipsychotics; particularly caution with electrolyte disturbances

Contraindications

  • Phaeochromocytoma
  • Prolactin-dependent tumours (e.g. pituitary adenoma, breast cancer)
  • eGFR <10
  • Concomitant QT-prolonging drugs (QT prolongation risk)
  • Hypersensitivity to amisulpride

Side effects

  • Hyperprolactinaemia (very common — causes galactorrhoea, amenorrhoea, gynaecomastia, sexual dysfunction)
  • QTc prolongation (dose-dependent)
  • Extrapyramidal side effects (less than typical antipsychotics but present)
  • Insomnia, agitation
  • Weight gain (less than olanzapine)
  • Constipation

Interactions

  • QT-prolonging drugs — contraindicated or caution (additive QT risk)
  • Levodopa — mutual antagonism — avoid if possible
  • CNS depressants — additive sedation

Monitoring

  • ECG (QTc) — baseline, during titration
  • Prolactin (if hyperprolactinaemia symptoms)
  • eGFR (dose adjustment required)
  • EPSE assessment
  • Weight and metabolic parameters

Reference: BNFc; BNF 90; NICE CG178 (Psychosis and Schizophrenia). Verify against your local formulary and the latest BNF before prescribing.

Related

Curated clinical cross-links plus same-class fallbacks.

Calculators
Pathways