Phenothiazine antipsychotic / antiemetic

Levomepromazine

Brand names: Nozinan

Levomepromazine is a phenothiazine antipsychotic used in palliative care for distressing symptoms such as nausea, vomiting and agitation, and also in the management of psychosis.

Dosing — being independently re-sourced

ClinCalc Pro is rebuilding its dose data from primary open sources — the manufacturer SmPC (eMC), the WHO Model Formulary and other official references — under clinician review. This drug's structured dose is not yet published here. Confirm all doses against the product SmPC and your local formulary before prescribing.

Clinical monograph

How it works

It antagonises dopamine D2 receptors and has additional antagonist activity at histamine, muscarinic, serotonergic and alpha-adrenergic receptors, contributing to its sedative and antiemetic effects.

Prescribing in practice

It commonly causes pronounced sedation and postural hypotension, so use cautiously and monitor blood pressure, particularly in frail or palliative patients.
Like other antipsychotics it can cause extrapyramidal effects and QT-interval prolongation.
In the elderly with dementia, antipsychotics increase the risk of stroke and death.

Monitoring

Monitor blood pressure for postural hypotension and observe for sedation, extrapyramidal symptoms and QT prolongation.

Counselling the patient

Warn that drowsiness is expected and may be marked.
Rise slowly from sitting or lying to reduce dizziness.
Report any abnormal movements or fainting.

Evidence & guidelines

Levomepromazine is widely used in UK palliative care for nausea and agitation, supported by established practice and palliative care guidance.

Reference: Palliative care formulary; Drug verified in RxNorm (NLM); confirm dosing against the manufacturer SPC (eMC). Verify against your local formulary and current prescribing references before prescribing. Monograph status: clinician-reviewed (2026-07-04).

Curated clinical cross-links plus same-class fallbacks.

Calculators

Pathways