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Updated 2 Feb 2023 | Antipsychotics

Drugs List

  • promazine 25mg tablets
  • promazine 25mg/5ml oral solution
  • promazine 50mg tablets
  • promazine 50mg/5ml oral solution
  • Dosage

    Dosage should be individually determined with regard to effectiveness and tolerance.

    Initiate therapy on a low dose and increase at frequent regular intervals until the desired response is obtained. The initiation and increase of dosage should be performed under close supervision.


    Psychomotor agitation
    100mg - 200mg four times per day.


    Psychomotor agitation
    Half the normal starting dose 50 - 100mg dose may be sufficient for a therapeutic response.

    Agitation and restlessness
    Initiate treatment on 25mg and increase, if necessary, up to 50mg four times a day.


    Contraindicated in children under 18 years old.

    Patients with Renal Impairment

    Use with caution. Initiate therapy on small doses in severe renal impairment and titrate slowly because of increased cerebral sensitivity.

    The Renal Drug Handbook suggests in patients with a glomerular filtration rate of below 10 ml/min start with a low dose and titrate slowly.

    Patients with Hepatic Impairment

    There is no specific dosing regimen, however, caution should be exercised as all antipsychotics may precipitate coma in hepatic impairment.


    Comatose conditions
    Central nervous system depression
    Bone marrow depression
    Breastfeeding (see Lactation section)
    Pregnancy (see Pregnancy section)
    Children under 18 years old

    Precautions and Warnings

    Use with caution in the following conditions:
    History of jaundice
    Renal impairment ( see Dosage in Renal Impairment )
    Hepatic impairment ( see Dosage in Hepatic Impairment )
    Parkinsonism and Parkinson's disease: May be exacerbated by antipsychotics
    Respiratory disease: Respiratory depression may occur
    Epileptic disorder and predisposition for epilepsy
    Myasthenia gravis
    Benign prostatic hypertrophy
    Predisposition to narrow angle glaucoma
    Cerebral arteriosclerosis

    Cardiac disease and arrhythmias - Promazine may cause QT prolongation. Persistently prolonged QT intervals may increase the risk of malignant arrhythmias. Use with caution in patients with hypokalaemia or hypomagnesaemia, a history of cardiovascular disorders, QT prolongation, significant bradycardia, recent acute myocardial infarction, uncompensated heart failure, or cardiac arrhythmia.

    Before starting treatment with promazine, consider an ECG with measurement of serum potassium and magnesium levels. Periodic serum electrolyte levels should be monitored and corrected if necessary, especially during long-term chronic usage. Sudden deaths have been reported.

    Elderly - reduce initial dose (such patients can be sensitive to extrapyramidal and hypotensive effects). The balance of risks and benefit should be considered before prescribing antipsychotic drugs for elderly patients. In elderly patients with dementia, antipsychotic drugs are associated with a small increased risk of mortality and an increased risk of stroke or transient ischaemic attack. Furthermore, elderly patients are particularly susceptible to postural hypotension and to hyper and hypothermia in hot or cold weather.
    It is recommended that: Antipsychotic drugs should not be used in elderly patients to treat mild to moderate psychotic symptoms and treatment should be reviewed regularly.

    Cases of venous thromboembolism (VTE) have been reported with antipsychotic medication. All possible risk factors for VTE should be identified before and during treatment and preventative measures taken. There is a possibility of increased risk of cerebrovascular adverse events in the dementia population.

    Patients should avoid alcohol.

    Avoid abrupt withdrawal. Acute withdrawal symptoms including nausea, vomiting, insomnia, extrapyramidal reactions have been reported following abrupt cessation of high doses of neuroleptics. Relapse may also occur.

    Haematological disorder - perform blood counts if the patient develops signs of unexplained infection or fever. Blood dyscrasias have been reported rarely.

    Prolonged and or high doses may lead to the occurrence of tardive dyskinesia particularly in the elderly. Neuroleptic therapy should be withdrawn if dyskinesia develops.

    Discontinue if patient develops neuroleptic malignant syndrome (hyperthermia, fluctuating level of consciousness, muscle rigidity, and autonomic dysfunction with pallor, tachycardia, labile blood pressure, sweating, and urinary incontinence). Signs of autonomic dysfunction such as sweating and arterial instability may precede the onset of hyperthermia and serve as early warning signs.

    Photosensitivity may occur with higher dosages. Advise patients to avoid direct sunlight.

    Examine eyes for defects in prolonged use (such as corneal opacities, lens opacities or purplish pigmentation).

    Phenothiazines may impair body temperature regulation. Caution should be observed in hot or cold weather.

    Antipsychotic drugs may increase prolactin secretion.

    Promazine tablets contain lactose and sucrose. Patients with rare glucose-galactose malabsorption, or lactose intolerance should not take this medicine.

    Promazine syrup contains liquid glucose and sucrose. Patients with rare hereditary problems of fructose intolerance, rare glucose-galactose malabsorption or sucrase-isomaltase insufficiency should not take this medicine. It may also be harmful to teeth.

    Some preparations (liquid) may contain hydroxybenzoate esters which may cause allergic reactions (possibly delayed).

    May impair alertness, especially at the start of treatment or following alcohol consumption.

    Effects such as drowsiness may impair the ability to perform skilled tasks such as driving or operating machinery. Patients should be advised accordingly.

    Pregnancy and Lactation


    Contraindicated in pregnancy.

    There is insufficient evidence of the safety of promazine in human pregnancy nor is there evidence from animal studies that it is free from hazard.

    Neonates exposed to antipsychotics during the third trimester are at risk of adverse reactions including extrapyramidal and/or withdrawal symptoms. Monitor newborns carefully.

    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 14-17 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 ( ).


    Contraindicated in breastfeeding. The safety of promazine in breastfeeding has not been established.

    NICE advises that Infants of mothers who are breastfeeding while taking psychotropic medication should be monitored for adverse reactions.

    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


    Advise patients to seek medical attention if unexplained fever, sore throat or malaise occur.

    Photosensitivity may occur. Advise patients to avoid direct sunlight.

    Potentiates the effect of alcohol. Advise patients to avoid alcohol, while on promazine therapy.

    Advise patients of the sedative effects which may impair the ability to drive or operate machinery.

    Side Effects

    Ventricular tachycardia
    Urinary retention
    Dry mouth
    Blurred vision
    Cholestatic jaundice
    Haemolytic anaemia
    Respiratory depression
    Difficulty in micturition
    Torsades de pointes
    Weight gain
    Excitement (paradoxical)
    Tardive dyskinesia
    Neuroleptic malignant syndrome
    ECG changes
    Menstrual disturbances
    Contact sensitisation
    Corneal opacities
    Lens opacities
    Purplish pigmentation of skin
    Purplish pigmentation of cornea, conjunctiva, retina
    Sexual dysfunction
    Glaucoma (closed angle)
    Cardiac arrest
    Deep vein thrombosis (DVT)
    Impaired consciousness
    Urinary hesitancy
    Blood dyscrasias
    Urinary incontinence
    Nasal stuffiness
    Abnormal liver function tests
    Ventricular fibrillation
    Prolongation of QT interval
    Allergic skin reactions
    Biliary stasis
    Withdrawal symptoms
    Increased prolactin
    Muscle rigidity
    Autonomic instability
    Gastro-intestinal disturbances
    Venous thrombosis
    T-wave changes
    Extrapyramidal effects
    Interference with temperature regulation
    Pulmonary embolism
    Drug withdrawal syndrome (neonatal)

    Withdrawal Symptoms and Signs

    Acute withdrawal symptoms including nausea, vomiting, insomnia, extrapyramidal (dyskinesia, akathisia, dystonia) reactions have been reported following abrupt cessation of high doses of neuroleptics. Relapse may also occur.


    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 ( ).

    Shelf Life and Storage

    Liquid preparations
    Store below 25 degrees C
    Protect from light

    Store below 25 degrees C
    Keep container tightly closed

    Further Information

    Phenothiazines differ somewhat in predominant action and side effects. Selection is influenced by the degree of sedation required and the patient's susceptibility to extrapyramidal side effects

    The Phenothiazine derivatives can be divided into 3 main groups
    Group 1: Chlorpromazine, levomepromazine (methotrimeprazine) and promazine, generally characterised by pronounced sedative effects and moderate antimuscarinic and extrapyramidal side-effects.

    Group 2: Pericyazine, pipothiazine and thioridazine, generally characterised by moderate sedative effects, marked antimuscarinic effects, but fewer extrapyramidal side-effects.

    Group 3: fluphenazine, perphenazine, prochlorperazine and trifluoperazine, generally characterised by fewer sedative effects, fewer antimuscarinic effects but more pronounced extrapyramidal side-effects than group 1 and 2

    Last Full Review Date: July 2011

    Reference Sources

    British National Formulary, 63rd Edition (2012) Pharmaceutical Press, London.

    BNF for Children (2011-2012) Pharmaceutical Press, London.

    Drugs During Pregnancy and Lactation: Treatment Options and Risk Assessment, 2nd edition (2007) ed. Schaefer, C., Peters, P. and Miller, R. Elsevier, London.

    Drugs in Pregnancy and Lactation: A Reference Guide to Fetal and Neonatal Risk, 9th edition (2011) ed. Briggs, G., Freeman, R. and Yaffe, S. Lippincott Williams & Wilkins, Philadelphia.

    Martindale: The Complete Drug Reference, 37th edition (2011) ed. Sweetman, S. Pharmaceutical Press, London.

    NICE guidance CG45 Antenatal and postnatal mental health; February 2007.

    Summary of Product Characteristics: Promazine syrup 25mg/5ml. Rosemont Pharmaceuticals Ltd. Revised February 2012.

    Summary of Product Characteristics: Promazine syrup 50mg/5ml. Rosemont Pharmaceuticals Ltd. February 2012.

    Summary of Product Characteristics: Promazine 25mg Tablets. Teva UK Ltd. Revised August 2009.

    Summary of Product Characteristics: Promazine 50mg Tablets. Teva UK Ltd. Revised August 2009.

    The Renal Drug Handbook. 3rd edition. (2009) ed. Ashley, C and Currie, Radcliffe Publishing Ltd, Abingdon.

    UK Drugs in Lactation Advisory Service.
    Available at:
    Last accessed: July 29, 2011.

    Drug Safety Update, MHRA June 2008
    Last accessed: July 29, 2011.

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