It is a low-potency antipsychotic (approximately half as potent as chlorpromazine) with strong analgesic, hypnotic and antiemetic properties that are primarily used in palliative care.

[2][3] Serious side effects include tardive dyskinesia, akathisia, abnormalities in the electrical cycle of the heart, low blood pressure and the potentially fatal neuroleptic malignant syndrome.

[2] Levomepromazine is frequently prescribed and valued worldwide in palliative care medicine for its multimodal action, to treat intractable nausea or vomiting, and for severe delirium/agitation in the last days of life.

[2][3] A 2010 systematic review compared the efficacy of levomepromazine with atypical antipsychotic drugs: Data are few and not high quality making it impossible to be confident about the effects for schizophrenia.

[3] Levomepromazine has prominent sedative and anticholinergic/sympatholytic effects (dry mouth, hypotension, sinus tachycardia, night sweats) and may cause weight gain.