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Chlorpromazine parenteral


Parenteral formulations of chlorpromazine hydrochloride

Drugs List

  • chlorpromazine 25mg/1ml injection
  • Therapeutic Indications


    Acute excitement
    Anxiety state
    Hiccough - intractable
    Nausea,vomiting in terminal care when other drugs ineffective/unavailable
    Paranoid psychosis
    Schizophrenia and autism in childhood
    Short term adjunctive management of violent/dangerously impulsive behaviour
    Short term moderate-severe psychomotor agitation (adjunctive management)


    Oral formulation is the preferred method of administration.


    Nausea and Vomiting due to terminal illness
    Initial dose: 25 mg.
    Then 25 mg to 50 mg every 3 to 4 hours until vomiting has stopped.

    Intractable Hiccup
    Initial dose: 25 mg to 50 mg.
    If the initial dose fails inject by slow intravenous infusion 25 mg to 50 mg of chlorpromazine in 500 ml to 1000 ml of sodium chloride.

    Schizophrenia, Anxiety, Agitation and other Psychoses
    Initial dose: 25 mg to 50 mg.
    Then use oral formulation.
    If deep intramuscular needs to be repeated, administer 25 mg to 50 mg every 6 to 8 hours.


    Schizophrenia, Anxiety, Agitation and other Psychoses
    Administer half or quarter of the adult dosage.
    If deep intramuscular needs to be repeated, administer 25 mg every 8 hours.


    Nausea and Vomiting due to terminal illness
    Children aged 13 to 18 years
    (See Dosage; Adult)

    Children aged 6 to 12 years
    0.5 mg/kg every 6 to 8 hours.
    Maximum daily dose: 75 mg.

    Children aged 1 to 5 years
    0.5 mg/kg every 6 to 8 hours.
    Maximum daily dose: 40 mg.

    Schizophrenia, Anxiety, Agitation and other Psychoses
    Children aged 13 to 18 years
    (See Dosage; Adult)

    Children aged 6 to 12 years
    0.5 mg/kg every 6 to 8 hours.
    Maximum daily dose: 75 mg.

    Children aged 1 to 5 years
    0.5 mg/kg every 6 to 8 hours.
    Maximum daily dose: 40 mg.

    Children under 1 year
    Use in only life saving conditions.


    Benign prostatic hyperplasia
    Cardiac failure
    Central nervous system depression
    Hepatic impairment
    History of agranulocytosis
    History of narrow angle glaucoma
    History of urinary retention
    Long QT syndrome
    Myasthenia gravis
    Parkinson's disease
    Renal impairment
    Torsade de pointes

    Precautions and Warnings

    Family history of long QT syndrome
    Predisposition to orthostatic hypotension
    Predisposition to venous thromboembolism
    Prolonged starvation
    Risk of cerebrovascular accident
    Tobacco smoking
    Cardiac disorder
    Cardiovascular disorder
    Chronic constipation
    Diabetes mellitus
    Electrolyte imbalance
    Epileptic disorder
    Haematological disorder
    History of cardiovascular disorder
    History of jaundice
    History of seizures
    History of torsade de pointes
    Organic brain syndrome
    Severe respiratory disease

    Correct electrolyte disorders before treatment
    Advise ability to drive/operate machinery may be affected by side effects
    Patients at risk of arrhythmias perform ECG prior to initiating therapy
    Reduce initial dose in the elderly
    Contains sodium metabisulfite. Caution,may cause allergic reactions
    Avoid contact of product with skin
    Do not use if solution is discoloured or particulates are apparent
    Keep patient supine when receiving injection
    Local pain or nodule formation may occur after intramuscular administration
    Perform ECG before and during treatment
    Discontinue treatment if patient develops seizures
    Examine eyes for defects in prolonged use
    Haematological monitoring required in long term use
    Hypothermia may develop in the elderly
    Monitor blood counts regularly
    Monitor blood glucose closely in patients with diabetes mellitus
    Monitor blood pressure
    Monitor patients at risk for signs & symptoms of venous thromboembolism
    Monitor serum electrolytes
    Neonate exposed in utero: Monitor neonate for adverse effects
    Perform blood counts if unexplained infection or fever develops
    Advise patient to report unexplained fever, sore throat, bruising, bleeding
    May cause postural hypotension especially in elderly
    May precipitate diabetes mellitus
    Predisposition QT prolongation: Counsel patient on symptoms of arrhythmias
    Avoid abrupt withdrawal
    Discontinue at first signs of jaundice
    Discontinue if fever occurs
    Discontinue if paralytic ileus occurs
    Discontinue if patient develops neuroleptic malignant syndrome
    Dose adjustment required if patient starts/stops smoking during therapy
    Not licensed for all indications in all age groups
    Advise that effects are potentiated by CNS depressants (including alcohol)
    Female: May cause infertility
    Advise patient that photosensitivity possible
    Advise patient to avoid exposure to direct sunlight

    Monitor patients for up to 2 years after discontinued as recurrence symptoms may be delayed.

    If an unexplained infection or fever occurs, perform a haematological investigation immediately.

    Pregnancy and Lactation


    Use chlorpromazine with caution in pregnancy.

    At the time of writing there is limited published information regarding the safety of chlorpromazine in human pregnancy. Animal studies have shown harmful effects, rodents, when exposed to high doses over long periods of time have shown the increased risk of embryotoxicity (Briggs et al, 2015). Schaefer (2015) states studies of chlorpromazine used in the first trimester of pregnancy showed no evidence of teratogenic effects but studies in high doses showed 3 infants to suffer from respiratory distress and die. Briggs (2015) states although chlorpromazine does cross the placenta, the majority of studies using chlorpromazine during pregnancy consider the drug to be safe to use in low doses over a short period of time. The manufacturer suggests chlorpromazine should be avoided during pregnancy unless the potential benefit to the mother outweighs the potential risk to the foetus.

    Antipsychotics used during the third trimester of pregnancy have been found to prolong labour and increase adverse effects to neonates including reactions of withdrawal symptoms and respiratory distress. It is advised to monitor newborns that have been exposed to antipsychotics during pregnancy.

    The use of all medication in pregnancy should be avoided whenever possible; particularly in the first trimester. Non-drug treatments should also be considered. When essential, a medication with the best safety record over time should be chosen, employing the lowest effective dose for the shortest possible time. Polypharmacy should be avoided. Teratogens taken in the pre-embryonic period, often quoted as lasting until 14 to 17 days post-conception, are believed to have an all-or-nothing effect. Where drugs have a short half-life, and when the date of conception is certain, this may allow women to be reassured where drug exposure has occurred within this time frame. Further advice may be available from the UK National Teratology Information Service (NTIS) and through ToxBase, available via password on the internet ( ) or if this is unavailable at the backup site ( ).


    Chlorpromazine is contraindicated in breastfeeding.

    Schaefer (2015) states chlorpromazine has a long half life of approximately 30 hours. Hale (2015) states chlorpromazine is excreted in breast milk in small amounts and due to its relatively long half life, it increases the potential risk to a breastfed infant if used in breastfeeding long term. Studies have shown infants who have been exposed to chlorpromazine via breastfeeding have became drowsy and lethargic (Briggs et al, 2015).
    The manufacturer suggests breastfeeding should be stopped during the use of chlorpromazine.

    Neonates, infants born prematurely, those with low birth weight, those with an unstable gastrointestinal function or who have serious illnesses may require special consideration. For any infant, if a drug is prescribed to the nursing mother, it should be at the lowest practical dose and for the shortest time. When drug administration is unavoidable and breastfeeding is to continue, minimisation of exposure of the infant to the drug may sometimes be achieved by timing the maternal doses to just after a feeding episode. Infants exposed to drugs via breast milk should be monitored for unusual signs or symptoms. Interactions between the drug received by the infant from the mother's milk and medication prescribed for the infant should also be considered, for example, when the drug given to the infant may prevent metabolism of the drug received via breast milk.
    Specialist advice is available from the UK Drugs in Lactation Advisory Service at

    Side Effects

    Acute dystonias
    Allergic reaction
    Anaphylactic reaction
    Antimuscarinic effects
    Aplastic anaemia
    Atrial arrhythmia
    Atrioventricular block
    Autonomic instability
    Cardiac arrest
    Cardiac arrhythmias
    Contact sensitisation
    Corneal opacities
    Decreased glucose tolerance
    Dry mouth
    ECG changes
    Extrapyramidal effects
    Gastro-intestinal disturbances
    Haemolytic anaemia
    Hypersensitivity reactions
    Impaired consciousness
    Lens opacities
    Liver damage
    Local pain (injection site)
    Menstrual disturbances
    Micturition disorders
    Nasal stuffiness
    Neuroleptic malignant syndrome
    Nodules (injection site)
    Ocular changes
    Postural hypotension
    Prolongation of QT interval
    Purplish pigmentation of cornea, conjunctiva, retina
    Purplish pigmentation of skin
    Respiratory depression
    Sexual dysfunction
    ST depression
    Sudden death reported
    Systemic lupus erythematosus
    T-wave changes
    Tardive dyskinesia
    Thrombocytopenic purpura
    U-wave changes
    Urinary incontinence
    Venous thrombosis
    Ventricular fibrillation
    Ventricular tachycardia
    Weight gain


    It is strongly recommended that the UK National Poisons Information Service be consulted on cases of suspected or actual overdose where there is doubt over the degree of risk or about appropriate management.

    The following number will direct the caller to the relevant local centre (0844) 892 0111

    Information may be obtained if you have access to ToxBase the primary clinical toxicology database of the National Poisons Information Service. This is available via password on the internet ( ) or if this is unavailable at the backup site ( ).

    Further Information

    Last Full Review Date: February 2017

    Reference Sources

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 3rd edition (2015) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 10th edition (2015) ed. Briggs, G., Freeman, R. Wolters Kluwer Health, Philadelphia.

    Joint Formulary Committee. British National Formulary (online) London: BMJ Group and Pharmaceutical Press. Accessed on 18 January 2018.

    Medications and Mothers' Milk, Sixteenth Edition (2014) Hale, T and Rowe, H, Hale Publishing, Plano, Texas.

    Paediatric Formulary Committee. BNF for Children (online) London: BMJ Group, Pharmaceutical Press, and RCPCH Publication. Accessed on 18 January 2018.

    Summary of Product Characteristics: Largactil Injection. Sanofi-Aventis Pharma. Revised July 2016.

    Specialist Pharmacy Service (SPS)
    Available at:
    What are the clinically significant drug interactions with tobacco smoking? Last revised: July 2020
    Last accessed: 07 December 2020

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