Healthy Matters
Resources
  • Healthy Matters
    Drugs A-Z
    Pharmacist Tips | Dosages | Side effects
  • Healthy Matters
    Food & Nutrition
    Nutritionist Tips | Facts | Precautions
  • Healthy Matters
    Chinese Medicine Herbs
    Practitioner Tips | Dosages | Side effects
  • Healthy Matters
    Chinese Medicine Prescriptions
  • Healthy Matters
    Expert Advisory Board
Articles
  • Healthy Matters
    Specialists Guide
  • Healthy Matters
    Other Services Guide
  • Healthy Matters
    Vaccination
  • Healthy Matters
    Parenting Guides
Health Topics
  • Healthy Matters
    Allergy & Immunology
  • Healthy Matters
    Baby & Child's Health
  • Healthy Matters
    Beauty
  • Healthy Matters
    Bone & Muscle Health
  • Healthy Matters
    Cancer & Tumor
  • Healthy Matters
    Common Illnesses
  • Healthy Matters
    Digestive Health
  • Healthy Matters
    Eye Health
  • Healthy Matters
    Fitness
  • Healthy Matters
    Food & Nutrition
  • Healthy Matters
    Heart & Vascular Health
  • Healthy Matters
    Infectious Diseases
  • Healthy Matters
    Medical Tests
  • Healthy Matters
    Mental Health
  • Healthy Matters
    Pregnancy
  • Healthy Matters
    Respiratory Health
  • Healthy Matters
    Sexual Health
  • Healthy Matters
    Skin Health
  • Healthy Matters
    Urological Health
  • Healthy Matters
    Women's Health
Healthy Offers
Health Check
  • Basic Health Screening for $1600 (Original: $3,120)
    Trinity Medical Centre
  • Premier Health Screening (Female) for $4,500 (Original: $9,120)
    Trinity Medical Centre
  • Premier Health Screening (Male) for $4,200 (Original: $8,760)
    Trinity Medical Centre
  • Stroke Risk Assessment for $7,100 (Original: 9,430)
    Trinity Medical Centre
  • Cardiac & Coronary Assessment for $5,800 (Original: $8,330)
    Trinity Medical Centre
  • Bone Health Screening for $1,600 (Original: $2,990)
    Trinity Medical Centre
Eye Health
  • Myopia Control Assessment for Children : Privileged Price - HK$400
    Clarity Eye Centres
  • Comprehensive Eye Examination Plan for Adult - HK$500
    Clarity Eye Centres
  • Comprehensive Eye Examination Plan (For SMILE PRO) - HK$400
    Clarity Eye Centres
  • Comprehensive Eye Examination Plan (For ICL) - HK$580
    Clarity Eye Centres
Healthy Matters
Search All
  • Healthy Matters
    Doctors
    Specialty | Address | Phone number
  • Healthy Matters
    Clinics
    Opening Hours | Address | Phone number
Popular Locations
  • Healthy Matters
    Central
  • Healthy Matters
    Tsim Sha Tsui
  • Healthy Matters
    Mong Kok
  • Healthy Matters
    Causeway Bay
Healthy Matters
Home
>
Western medicines > Promethazine

Promethazine

Chinese name:
異丙嗪
Joseph Blais, Pharmacist
Reviewed by
Joseph Blais, Pharmacist
Expert Advisory Board Member
Last Updated: 2022-04-29

What is Promethazine for?

Promethazine is a sedating (first generation) antihistamine. It has a wide range of uses including treating allergic conditions, inducing sedation, 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 coughs and colds.

How to use it?

The oral doses for different age groups and uses are listed below:

 

For allergic conditions

Adult
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

Adult
As Promethazine HCl: 20-50 mg at night.

 

For nausea and vomiting

Adult
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

Adult
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.

Who should not take Promethazine?

  • People with an allergy to Promethazine or other ingredients of the formulation
  • Children under the age of 2

Pharmacist Tips:

  • Avoid taking Promethazine if you are 65 years and older as you are at higher risk of side effects, such as confusion, dry mouth and constipation.
  • As Promethazine can cause drowsiness, do not drive or operate machinery if affected.

Common dosing schedule: 
You can take Promethazine with food to reduce gastrointestinal upset.

 

This schedule is for reference only, adjustments may be made according to individual needs.

 

Some common medications Promethazine may interact with:

  • Alcohol
  • Clozapine
  • Flunitrazepam
  • Ipratropium
  • Other antihistamine, e.g. Chlorpheniramine, Fexofenadine, Levocetirizine, Loratadine

Please notify your doctor or pharmacist if you are taking the above medication, dosage adjustments might be needed.

Where to buy Promethazine in Hong Kong?

In Hong Kong, Promethazine is an over-the-counter medicine which can be purchased without a prescription from any retail outlet in Hong Kong. This includes grocery stores, convenience stores, 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 https://www.drugoffice.gov.hk

Need more information?

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.

Healthy Matters

Your health resource, made in Hong Kong

Healthy Matters is Hong Kong’s leading health resource. Our mission is to help you make better health decisions and take control of your health.

 

Our team of experts is committed to producing reliable health content that is accurate, engaging and relevant, to cover your health & wellness journey from prevention to treatment.

 

Whether you are looking for trusted information on health conditions, wellbeing or looking for the right doctor or service in Hong Kong, we’re here to help!

 

Your health matters. Begin your health journey with Healthy Matters today!

 

Read about our story

illustrations of a doctor and a mobile phone