Drug reference

Amisulpride

Atypical Antipsychotic · Antipsychotic

Also known as Sulpitac, Amisant, Solian

START

Confirm schizophrenia diagnosis with positive and/or negative symptoms. Baseline ECG (QTc), prolactin, fasting glucose, weight. Screen for pheochromocytoma and prolactin-dependent tumors. Start at low dose.

TYPICAL MAX

1200 mg/day (adults); 400 mg/day (elderly). QT risk increases >800 mg/day.

STOP IF

QTc >500 ms or increase >60 ms from baseline, NMS, severe TD, agranulocytosis, signs of pheochromocytoma crisis

WATCH

ECG at baseline and after dose increases (QTc), prolactin levels (if symptomatic), EPS (AIMS scale), weight/glucose (baseline, 12 weeks), renal function (dose adjustment)

CDSCO approvedSchedule HATC N05AL05

Dose laddermg/d

Renal dose adjustmenteGFR mL/min/1.73m²

KDIGO 2024 + manufacturer label

Pharmacokineticsplasma · t hours

ONSET: 23min · absorption onset
PEAK: 1.5h · 1-2 h (oral)
t½: 12h · ~12 h (single); 16-30 h (steady-state)
DURATION: 12h · 12 h (BID dosing)

EXCRETION

~50% renal unchanged; minimal hepatic metabolism; NOT CYP-dependent

route + CYP

INTERACTIONS

12 major

incl. contraindicated

PREGNANCY

FDA PLLR: Not approved in US (EU/India use). Animal studies showed adverse effects. Limited human data. Hyperprolactinemia may affect fertility. Use only if benefit clearly outweighs risk.

FDA category + note

Top interactionssee all 12 →

AmiodaroneContraindicatedDatabaseDDInter
CisaprideContraindicatedDatabaseDDInter
DisopyramideContraindicatedDatabaseDDInter
ErythromycinContraindicatedDatabaseDDInter

Available in India

361 branded formulations. Look up specific brands in the Drugs workspace.

Mechanism

Amisulpride is a substituted benzamide atypical antipsychotic with high selectivity for dopamine D2 and D3 receptors. At low doses (50-300 mg/day), it preferentially blocks presynaptic D2/D3 autoreceptors, enhancing dopaminergic transmission in the mesocortical pathway — this accounts for its efficacy in negative symptoms of schizophrenia and dysthymia. At higher doses (400-1200 mg/day), it blocks postsynaptic D2/D3 receptors in the mesolimbic pathway, reducing positive symptoms of schizophrenia. It has minimal affinity for 5-HT2A, alpha-1, H1, and muscarinic receptors, resulting in a relatively clean side effect profile with low sedation, minimal weight gain, and reduced metabolic effects compared to other atypical antipsychotics. It does not cross the blood-brain barrier extensively in areas responsible for motor control, reducing extrapyramidal symptoms.

Indications

Schizophrenia — acute and chronic (positive and negative symptoms)Predominant negative symptoms of schizophrenia (low doses)Acute psychotic episodesDysthymia (low doses — off-label in some regions)Treatment-resistant schizophrenia (high doses, off-label)

Dosing

Adult: Acute psychotic episodes: 400-800 mg/day in 2 divided doses; max 1200 mg/day. Predominant negative symptoms: 50-300 mg/day. Chronic schizophrenia: 400-600 mg/day. Elderly: start ¼-½ normal dose; titrate slowly.
Pediatric: Not recommended <15 years.
Renal adjustment: CrCl 30-60: reduce dose by 50%. CrCl 10-30: reduce dose by 75%. CrCl <10: not recommended (limited data; may accumulate).
Hepatic adjustment: No adjustment required (minimal hepatic metabolism).
Geriatric: Start at ¼-½ normal dose (50-200 mg/day); max 400 mg/day. Increased risk of sedation, QT prolongation, and EPS.
Max dose: 1200 mg/day (adults); 400 mg/day (elderly)

Pharmacokinetics

Onset

Antipsychotic effect: 1-2 weeks for symptom improvement; 4-6 weeks for full effect.

Peak effect

Oral: peak plasma at 1-2 hours (rapid absorption). Steady-state: 2-3 days.

Duration

12 hours (supports BID dosing).

Half-life

~12 hours (single dose); 16-30 hours at steady-state. 2-fold accumulation at steady-state.

Bioavailability

~48% (oral; reduced by food — take before meals).

Protein binding

~16% (low; primarily to albumin). Low protein binding means minimal displacement interactions.

Metabolism

Minimal hepatic metabolism (~50% excreted unchanged). Two inactive metabolites produced in small amounts. NOT a CYP substrate — very few CYP-mediated drug interactions.

Excretion

Renal: ~50% unchanged in urine. Fecal: ~20%.

Contraindications

Hypersensitivity to amisulpride or substituted benzamides
Pheochromocytoma (risk of hypertensive crisis — amisulpride may increase catecholamine release)
Prolactin-dependent tumors (prolactinoma, breast cancer)
Severe renal impairment (CrCl <30) — dose reduction required
Concomitant use with levodopa (dopamine receptor antagonism opposes levodopa effects)
QT prolongation, congenital long QT syndrome, or concurrent QT-prolonging drugs

Side effects

Common

Insomnia, agitation, anxietyWeight gain (less than other atypicals — mean 1-2 kg)Hyperprolactinemia (galactorrhea, amenorrhea, sexual dysfunction, gynecomastia — dose-related, more common than other atypicals)EPS at high doses (>400 mg/day): akathisia, parkinsonism, dystoniaNausea, constipation, dry mouthElevated prolactin levels

Serious

QT prolongation and torsades de pointes (dose-related; especially at doses >800 mg/day or in CYP poor metabolizers)
Neuroleptic malignant syndrome (NMS)
Tardive dyskinesia (TD)
Agranulocytosis (rare)
Seizures (dose-dependent lowering of seizure threshold)
Veno-occlusive disease (rare)
Hyperglycemia/diabetes (less common than olanzapine/clozapine but reported)

Pregnancy & lactation

Pregnancy

FDA PLLR: Not approved in US (EU/India use). Animal studies showed adverse effects. Limited human data. Hyperprolactinemia may affect fertility. Use only if benefit clearly outweighs risk.

Lactation

Excreted in breast milk. Hyperprolactinemia may suppress lactation. Avoid breastfeeding if possible. If necessary, monitor infant for EPS, sedation, and developmental effects.

Drug interactions

Amiodarone

Contraindicated

Database

Increased risk of Torsades de Pointes (TdP) and other ventricular arrhythmias