King Edward Memorial Hospital
Adult Medication Monograph
ADULT Medication Monograph
PROMETHAZINE HYDROCHLORIDE
This document should be read in conjunction with this DISCLAIMER
Formulary: Unrestricted
Class Sedating antihistamine
Presentation Tablet: 10mg, 25mg
Ampoule: 50mg/2mL
*Note: NOT for IV, IA or subcut administration. Promethazine is
highly caustic and extravasation may cause pain, paralysis and
necrosis.
Storage Store at room temperature, below 25°C. Protect from light.
Dose Nausea and Vomiting
Oral:
25mg every four to six hours when required (Max dose 100mg daily)
IM:
12.5-25mg every four to six hours when required (Max dose 100mg
daily).
Sedation
Oral:
25-75mg as a single dose.
For short-term use under medical supervision. Give 1-2 hours before
procedure or as a single dose at night.
Allergy
Oral:
25-75mg once daily OR 10-25mg TWO or THREE times daily
IM:
25-50mg as a single dose
Adult Medication Monograph Page 1 of 4
Promethazine - Adult
Administration Oral (preferred route)
Swallow whole with a glass of water. Can be crushed and dispersed
in water if patient has swallowing difficulty.
IM
Inject deep into a large muscle
*Note: NOT for IV, IA or subcut administration. Promethazine is
highly caustic and extravasation may cause pain, paralysis and
necrosis.
Pregnancy 1st Trimester: Safe to use
2nd Trimester: Safe to use
3rd Trimester: Safe to use
Breastfeeding Consider alternative
Monitoring Sedation
Clinical Guidelines KEMH Clinical Guidelines:
and Policies Pregnancy Care: First Trimester Complications
Postoperative Anaesthetics
Palliative Care
Discomforts in Pregnancy: Common
References Australian Medicines Handbook. Promethazine. In: Australian
Medicines Handbook [Internet]. Adelaide (South Australia):
Australian Medicines Handbook; 2020 [cited 2020 Sep 10]. Available
from: https://amhonline.amh.net.au/
The Royal Women's Hospital. Promethazine. In: Pregnancy and
Breastfeeding Medicines Guide [Internet]. Parkville (Victoria): The
Royal Women's Hospital; 2020 [cited 2020 Sep 10]. Available from:
https://thewomenspbmg.org.au/
Society of Hospital Pharmacists of Australia. Promethazine. In:
Australian Injectable Drugs Handbook [Internet]. [St Leonards, New
South Wales]: Health Communication Network; 2020 [cited 2020 Sep
10]. Available from: http://aidh.hcn.com.au
Adult Medication Guideline Page 2 of 4
Promethazine - Adult
Keywords: Promethazine, antihistamine, sedation, allergy, nausea, Phenergan, hyperemesis,
morning sickness
Publishing: Intranet Internet
Document owner: Chief Pharmacist
Author / Reviewer: KEMH Pharmacy Department
Date first issued: May 2015 Version: 4.0
Last reviewed: September 2020 Next review date: Sep 2023
Endorsed by: Medicines and Therapeutics Committee Date: Dec 2017
Standards Applicable: NSQHS Standards: 1 Governance, 4 Medication Safety
Printed or personally saved electronic copies of this document are considered uncontrolled.
Access the current version from the WNHS website.
For any enquiries relating to this guideline, please email KEMH.PharmacyAdmin@health.wa.gov.au
© Department of Health Western Australia 2020
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Promethazine - Adult
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