promazine hydrochloride at a glance
Medicine class
Phenothiazine antipsychotic
Licensed role
Short-term adjunctive management of moderate to severe agitation and restlessness where there is risk of harm
Form
Prescription-only oral syrup
What is promazine hydrochloride used for?
The selected UK product is licensed only as an adjunct to non-pharmacological interventions.
Short-term management of moderate to severe agitation and restlessness when there is a risk of harm to the individual or others.
How does promazine hydrochloride work?
Promazine reduces dopamine signalling and depresses activity within the central nervous system. Alpha-adrenergic blockade and weaker anticholinergic effects also contribute to calming effects and adverse effects such as low blood pressure, dry mouth and constipation.
promazine hydrochloride preparations and strengths
Syrup
Route: Oral
Strengths: 25 mg/5 mL, 50 mg/5 mL
How to take promazine hydrochloride
Take the syrup by mouth exactly as prescribed. Measure it carefully with an appropriate oral dosing device. Avoid alcohol because it can increase sedation and impairment.
Check the pharmacy label before each administration.
Use an oral measuring device where required.
Do not stop suddenly unless urgent medical care instructs you to do so.
promazine hydrochloride side effects
Common or expected effects
- Drowsiness, sedation or dizziness
- Dry mouth or constipation
- Blurred vision
- Low blood pressure, particularly on standing
- Headache or stomach upset
- Weight gain
- Blocked nose
- Menstrual, sexual or breast-related effects
Get urgent medical advice
- High temperature, severe muscle stiffness and altered consciousness
- Severe allergic reaction
- Fast or irregular heartbeat, fainting or chest pain
- Seizure
- Uncontrolled or abnormal movements
- Fever, sore throat or mouth ulcers suggesting a blood disorder
- Jaundice
- Symptoms of a blood clot, including a painful swollen leg or sudden breathlessness
- Acute painful blurred vision
promazine hydrochloride in pregnancy
The selected product should not be used during pregnancy, particularly early pregnancy, unless there are compelling clinical reasons. Specialist review is important if pregnancy is planned or confirmed. Exposure near delivery can cause movement, muscle-tone, breathing, feeding or withdrawal symptoms in the newborn, requiring monitoring after birth.
promazine hydrochloride while breastfeeding
Breastfeeding is contraindicated in the selected product information because promazine and its metabolites can enter milk. A prescriber or specialist breastfeeding-medicines service should review treatment rather than stopping it abruptly without advice.
promazine hydrochloride interactions
Promazine has clinically important sedative, cardiovascular, neurological and anticholinergic interactions. Check prescribed, non-prescription and herbal products with a pharmacist or prescriber.
Alcohol, opioids, sleeping medicines, anaesthetics and other CNS depressants
Sedation, impaired alertness and respiratory or central nervous system depression may be increased.
QT-prolonging medicines, including some antiarrhythmics, antibiotics, antidepressants and antipsychotics
The combination can increase the risk of dangerous ventricular arrhythmias.
Antihypertensives
Blood-pressure-lowering effects may be enhanced, increasing dizziness, falls or fainting.
Common questions about promazine hydrochloride
Answers are fully visible for fast scanning and source review.
What is promazine hydrochloride used for?
The selected UK syrup is licensed for short-term adjunctive management of moderate to severe agitation and restlessness when there is a risk of harm.
Is promazine hydrochloride the same as promethazine?
No. Promazine is an antipsychotic, whereas promethazine is a sedating antihistamine; similar names have contributed to prescribing and dispensing errors.
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.