Amisulpride

How it works

It is a selective antagonist at dopamine D2 and D3 receptors. At lower doses it preferentially blocks presynaptic autoreceptors, while at higher doses postsynaptic blockade predominates, which is reflected in its dose-related clinical and adverse effects.

Prescribing in practice

• It causes dose-dependent prolongation of the QT interval; assess cardiac risk factors, avoid co-prescribing with other QT-prolonging drugs where possible, and consult the SPC on ECG monitoring.
• It is largely excreted unchanged by the kidneys, so the dose must be reduced in renal impairment to avoid accumulation.
• It commonly causes marked hyperprolactinaemia, and extrapyramidal effects become more prominent at higher doses.

Monitoring

Monitor renal function and adjust dosing accordingly, and obtain ECGs to assess QT interval, particularly with cardiac risk factors. Review for symptoms of raised prolactin (such as galactorrhoea, menstrual disturbance or sexual dysfunction) and for extrapyramidal effects, alongside standard antipsychotic metabolic monitoring.

Counselling the patient

• Report a fast, slow or irregular heartbeat, fainting or palpitations promptly.
• Tell your prescriber about breast tenderness or discharge, changes in periods, or sexual problems, which can be caused by this medicine.
• Report any uncontrolled movements, tremor or muscle stiffness.

Evidence & guidelines

An established second-generation antipsychotic recommended within UK guidance (NICE) for schizophrenia, with QT prolongation a recognised dose-dependent class concern.