Medicines & Supplements A to Z > Chlorhexidine


Last updated on 19/03/2021.

Overview   |   Dosage   |    Side Effects   |   Precautions  |   Tips  |   Where To Buy  

GENERIC NAME: Chlorhexidine


BRAND NAME(S) IN HONG KONG: Cedium, Corsodyl, Ecolab, Hydrex

DRUG CLASS: Topical antimicrobial

USED FOR: Maintain oral hygiene, gingivitis, antiseptic to prevent skin infection

OTHER DRUGS IN THE SAME CLASS: Cetylpyridinium Chloride, Chlorine Dioxide

AVAILABLE DOSAGE FORMS: 0.2% (mouthwash)

What is Chlorhexidine for?

Chlorhexidine is a disinfectant and antiseptic. It has various uses including maintaining oral hygiene, managing oral thrush, gingivitis, aphthous ulcers (canker sores), ulcers due to denture, skin or wound cleansing, and as a surgical scrub. 

How to use it?

Chlorhexidine is available as a mouthwash, dental gel, and spray. It is also an ingredient in solutions and suppositories.

If you are using mouthwash, you should rinse or gargle 10 mL twice daily for 1 minute each time. Note that if you are using mouthwash for denture ulcer, you should cleanse and soak your dentures in mouthwash solution for 15 minutes twice daily. 

If you are using dental gel, you should apply 1-2 times daily by brushing the gel on your teeth. 

If you are using mouth spray, you should spray on your teeth, gingival or ulcer surfaces up to 12 sprays twice daily if necessary. 

If you are using the solution for wound cleansing, you should rinse your wound with water first, then apply a 4% solution to cover and wash your wound gently, and finally rinse. 

If you are using the solution for a surgical hand scrub, you should apply 5mL 4% solution and scrub for 3 minutes, then rinse repeatedly and dry.

What are the side effects of Chlorhexidine?

Common side effects of Chlorhexidine include dry mouth, mouth disorders, altered taste, tongue discolouration and tooth discolouration. 

Who should not take Chlorhexidine?

Anyone who has an allergy to Chlorhexidine.

Pharmacist Tips:

Do not rinse, brush or eat immediately after use.

Common dosing schedule:
Chlorhexidine is used in the morning and evening after brushing teeth.

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

Some common medications Chlorhexidine may interact with:
Chlorhexidine is not known to have significant interactions with other medications. 

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

Where to buy Chlorhexidine in Hong Kong?

In Hong Kong, Chlorhexidine is an over-the-counter medicine and 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

Need more information?

For detailed information about the use of Chlorhexidine 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.