Generic Medicine Info
Indications and Dosage
Intramuscular, Intravenous, Subcutaneous
Anxiety, Pain, Restlessness
Adult: Palliative care for the management of pain and accompanying distress (e.g. restlessness, agitation) in terminally ill patients: As levomepromazine hydrochloride: 12.5-25 mg via IM or IV inj. In case of severe agitation, doses of up to 50 mg 6-8 hourly may be administered. Alternatively, 25-200 mg daily may be given by continuous SC infusion over 24 hours via a syringe driver. Patient must remain in bed especially when receiving high initial doses. Dosage may vary according to the patient's condition and individual response.

Adult: Alternative treatment to chlorpromazine particularly when reduced psychomotor activity is desirable: As levomepromazine maleate: Ambulant patients: Initially, 25-50 mg daily in 3 divided doses; with the larger dosage portion taken at bedtime. Gradually increase dose according to individual response and tolerability. Non-ambulant or bed patients: Initially, 100-200 mg daily in 3 divided doses; gradually increased to 1,000 mg daily if needed. Patient must remain in bed especially when receiving high initial doses. Reduce dose to adequate maintenance level when the patient is stable.
Child: ≥10 years As levomepromazine maleate: 12.5-25 mg daily in divided doses. Max: 37.5 mg daily.

Anxiety, Pain, Restlessness
Adult: Palliative care for the management of pain and accompanying distress (e.g. restlessness, agitation) in terminally ill patients: Monotherapy or adjunctive therapy: As levomepromazine maleate: 12.5-50 mg 4-8 hourly. Patient must remain in bed especially when receiving high initial doses. Dosage may vary according to the patient’s condition and individual response.
IM/IV inj: Dilute required dose with an equal volume of 0.9% NaCl solution. Continuous SC infusion: Doses must be diluted with the calculated volume of 0.9% NaCl solution.
Comatose state, CNS depression, blood dyscrasia, phaeochromocytoma, history of agranulocytosis.
Special Precautions
Patient with CV disease, heart failure, risk factors for QT interval prolongation (e.g. personal or family history, bradycardia, 2nd- or 3rd-degree heart block, hypokalaemia, hypomagnesaemia, hypocalcaemia, history of ventricular arrhythmia or torsades de pointes); diabetes mellitus or its risk factors, hypothyroidism, myasthenia gravis, Parkinson's disease, seizure disorders, brain damage, alcoholism; predisposition to aspiration pneumonia (e.g. Alzheimer's disease), respiratory disease (eg, severe asthma, emphysema); decreased gastrointestinal motility, urinary retention, risk of urinary retention related to urethroprostatic disorders, benign prostatic hyperplasia, xerostomia, susceptibility to angle-closure glaucoma, or visual problems; at risk of stroke, thromboembolism, hypotension or condition where a transient hypotensive episode is poorly tolerated (e.g. cerebrovascular disease). Patient subjected to heat exposure, strenuous exercise, or dehydration. Not indicated for use in dementia or dementia-related psychosis in the elderly. Tab: Concomitant use with dopaminergic agents (except in patients with Parkinson's disease). Avoid abrupt withdrawal. Severe renal and hepatic impairment. Children, elderly, and debilitated patients. Pregnancy and lactation.
Adverse Reactions
Significant: Anticholinergic effects (e.g. blurred vision, xerostomia, constipation, urinary retention), CNS depression, extrapyramidal symptoms, including akathisia, tardive dyskinesia, pseudoparkinsonism and acute dystonic reactions; falls, ocular effects with prolonged use (e.g. lenticular and corneal deposit, pigmentary retinopathy), oesophageal dysmotility and aspiration, paralytic ileus; orthostatic hypotension (particularly with high doses or after parenteral use), hyperglycaemia or impaired glucose tolerance, diabetic ketoacidosis, blood dyscrasias (e.g. granulocytopenia, neutropenia, agranulocytosis), neuroleptic malignant syndrome (NMS), impaired core body temperature regulation; hyperprolactinaemia, decreased seizure threshold. Rarely, QT prolongation; priapism.
General disorders and administration site conditions: Asthenia, heat stroke (particularly in hot and humid conditions).
Hepatobiliary disorders: Hepatocellular, cholestatic or mixed liver injury. Rarely, jaundice.
Investigations: ECG changes.
Metabolism and nutrition disorders: Hyponatraemia, syndrome of inappropriate antidiuretic hormone secretion (SIADH).
Nervous system disorders: Somnolence, sedation.
Psychiatric disorders: Confusional state, delirium.
Skin and subcutaneous tissue disorders: Photosensitivity reaction, allergic dermatitis.
Vascular disorders: Hypotension.
Potentially Fatal: Arrhythmias (e.g. ventricular arrhythmias of torsades de pointes type); venous thromboembolism including pulmonary embolism and DVT. Rarely, necrotising enterocolitis.
Parenteral/PO: C
Patient Counseling Information
This drug may cause drowsiness, confusion, disorientation, or excessive hypotension; if affected, do not drive or operate machinery.
Monitoring Parameters
Monitor mental status; vital signs as clinically indicated; BMI, waist circumference; LFTs at baseline and regularly thereafter; CBC at baseline, during the 1st 2-3 months of treatment and periodically thereafter; serum electrolytes (e.g. Ca, K, Mg), fasting plasma glucose level/HbA1c and lipid panel at baseline and as clinically indicated; ECG prior to treatment initiation then as needed. Perform ocular examination yearly in patients >40 years or every 2 years in younger patients. Assess for involuntary movements or parkinsonian signs, tardive dyskinesia and changes in vision. Closely monitor patients at high risk of suicidal ideation.
Symptoms: Drowsiness, loss of consciousness, hypotension, tachycardia, ECG changes, ventricular arrhythmias, hypothermia, convulsions, and severe extrapyramidal dyskinesias. Management: Supportive treatment. Perform gastric lavage within 6 hours after ingestion of toxic doses; administer activated charcoal. For generalised vasodilatation that may lead to circulatory collapse, may raise patient's legs; in severe cases, give IV fluids for volume expansion. If fluid replacement is insufficient to correct circulatory collapse, consider positive inotropic agents (e.g. dopamine). Restore normal body temperature and correct circulatory or metabolic disturbances for ventricular or supraventricular arrhythmias. Provide airway maintenance or assisted respiration (in extreme cases) for pronounced CNS depression. Administer IV diazepam for convulsions and IV or IM procyclidine or orphenadrine for severe dystonic reactions. Cool patients or give dantrolene Na for NMS.
Drug Interactions
May result in mutual antagonism when given with dopaminergic agents. Increased risk of arrhythmia with agents that prolong QT interval such as certain class IA and III antiarrhythmics (e.g. quinidine, disopyramide, amiodarone, sotalol), antimicrobials (e.g. moxifloxacin, erythromycin IV), TCAs, tetracyclic antidepressants (e.g. maprotiline), other neuroleptics (e.g. phenothiazines, pimozide), antihistamines (e.g. terfenadine, cisapride, bretylium and antimalarials (e.g. quinine, mefloquine). May potentiate CNS depressant effects with other sedatives, barbiturates. May cause electrolyte imbalance with diuretics. May increase the plasma concentrations of drugs mainly metabolised by CYP2D6 (e.g. amitriptyline). May cause transient metabolic encephalopathy when given with deferoxamine and prochlorperazine. Enhanced anticholinergic effects with other anticholinergic drugs.
Food Interaction
May enhance CNS depressant effects with alcohol.
Lab Interference
May cause false-positive or negative results in pregnancy tests.
Mechanism of Action: Levomepromazine is a phenothiazine neuroleptic with pharmacologic action similar to chlorpromazine and promethazine. The exact mechanism of activity is unknown; however, it exhibits strong sedative effects and possesses analgesic, antiemetic, antihistamine, and anti-epinephrine activity.
Synonym: methotrimeprazine.
Absorption: Time to peak plasma concentration: Approx 1-3 hours (oral); 0.5-1.5 hours (IM).
Distribution: Enters breastmilk (small amounts).
Excretion: Via urine and faeces. Elimination half-life: Approx 30 hours.
Chemical Structure

Chemical Structure Image

Source: National Center for Biotechnology Information. PubChem Compound Summary for CID 72287, Levomepromazine. https://pubchem.ncbi.nlm.nih.gov/compound/Levomepromazine. Accessed Aug. 31, 2021.

Store below 25°C. Protect from light.
MIMS Class
Analgesics (Non-Opioid) & Antipyretics / Antipsychotics
ATC Classification
N05AA02 - levomepromazine ; Belongs to the class of phenothiazine antipsychotics with aliphatic side-chain.
Anon. Levomepromazine. Lexicomp Online. Hudson, Ohio. Wolters Kluwer Clinical Drug Information, Inc. https://online.lexi.com. Accessed 29/07/2021.

Buckingham R (ed). Levomepromazine. Martindale: The Complete Drug Reference [online]. London. Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 29/07/2021.

Joint Formulary Committee. Levomepromazine. British National Formulary [online]. London. BMJ Group and Pharmaceutical Press. https://www.medicinescomplete.com. Accessed 29/07/2021.

Max Health Ltd. Levomepromazine Hydrochloride 25 mg/mL Injection data sheet 03 October 2018. Medsafe. http://www.medsafe.govt.nz. Accessed 29/07/2021.

Nozinan 25 mg Tablets (Aventis Pharma Limited Trading as Sanofi). MHRA. https://products.mhra.gov.uk. Accessed 29/07/2021.

Nozinan 25 mg/mL Solution for Injection/Infusion (Aventis Pharma Limited Trading as Sanofi). MHRA. https://products.mhra.gov.uk. Accessed 29/07/2021.

Sanofi Aventis New Zealand Limited. Nozinan 25 mg and 100 mg Tablets data sheet 12 March 2020. Medsafe. http://www.medsafe.govt.nz. Accessed 29/07/2021.

Disclaimer: This information is independently developed by MIMS based on Levomepromazine from various references and is provided for your reference only. Therapeutic uses, prescribing information and product availability may vary between countries. Please refer to MIMS Product Monographs for specific and locally approved prescribing information. Although great effort has been made to ensure content accuracy, MIMS shall not be held responsible or liable for any claims or damages arising from the use or misuse of the information contained herein, its contents or omissions, or otherwise. Copyright © 2024 MIMS. All rights reserved. Powered by MIMS.com
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