Medicines & Supplements A to Z > Promethazine
Last updated on June 27, 2019.
GENERIC NAME: Promethazine
CHINESE NAME: 異丙嗪
COMMON BRANDS IN HONG KONG: Axcel, Fenamin, Promegan, Synvomin
What is Promethazine for?
Promethazine is a sedating (first generation) antihistamine. It has a wide range of uses including treating allergic conditions, inducing sedation, as short-term management of insomnia, treating nausea and vomiting, and preventing and treating motion sickness. Antihistamines can also be used to manage the symptoms of the common cold such as runny nose and sneezing. Promethazine relieves symptoms of itching, runny nose, watery eyes and sneezing.
In Hong Kong, it is frequently found in combination products used for treating cough and cold.
How to use it?
The oral doses for different age groups and uses are listed below:
For allergic conditions
As Promethazine HCl: 25 mg at night, increase if necessary to 25 mg twice daily OR 10-20 mg 2-3 times daily
Child 2-5 years
As Promethazine HCl: 5-15 mg daily in 1-2 divided doses.
Child 5-10 years
As Promethazine HCl: 10-25 mg daily in 1-2 divided doses.
For short-term management of insomnia
As Promethazine HCl: 20-50 mg at night.
For nausea and vomiting
As Promethazine teoclate: 25 mg at night, may increase the dose to 50-75 mg at night or to 25 mg 2-3 times daily if necessary up to a maximum of 100 mg daily
For prevention of motion sickness
As Promethazine HCl: 20 or 25 mg the night before travelling and repeat in the next morning if necessary.
As Promethazine teoclate: 25 mg at night or 1-2 hour before travelling.
Child 2-5 years
As Promethazine HCl: 5 mg the night before the journey and repeat in the next morning (after 6-8 hours) if necessary.
Child 5-10 years
As Promethazine HCl: 10 mg the night before the journey and repeat in the next morning (after 6-8 hours) if necessary.
As Promethazine teoclate: 12.5 mg the night or 1-2 hour before travelling.
What are the side effects of Promethazine?
Common side effects of Promethazine include dizziness and drowsiness, constipation, blurred vision, and dry mouth. Avoid driving and operating machinery until you know how you respond to Promethazine.
Where to buy Promethazine in Hong Kong?
In Hong Kong, Promethazine is an over-the-counter medicine. It can be purchased without a prescription from medicine shops and pharmacies. It can also be obtained from doctors. To find a pharmacy near you, refer to the list of pharmacies (“Authorized Sellers of Poisons”) from the Hong Kong Department of Health.
For more information about drug names and ingredients, you can visit Hong Kong’s Drug Office at http://www.drugoffice.gov.hk
For detailed information about the use of Promethazine in children, pregnancy and breastfeeding, and for questions about drug interactions, please check with your pharmacist or doctor.
Disclaimer: our goal is to provide you with the most relevant drug information and common dosage for Hong Kong. This information does not constitute medical advice. For specific treatment recommendations and advice, always discuss with your doctor or pharmacist, and follow the instructions included with your specific medicine.