This NHS content is written for people in England. Medicine names, availability, prescribing and services may differ in other countries.
Dosage and how to use chlorhexidine
Dosage and how to use lozenges
The usual dose of chlorhexidine lozenges for children aged 12 years and over is up to 5 lozenges a day. Adults can have up to 10 lozenges a day.
Put a lozenge in your mouth and let it melt slowly.
Wait at least 30 minutes before having something to eat or drink.
Dosage and how to use mouthwash
The usual dose is 10ml, twice a day.
Pour 10ml into the measuring cup. Rinse the mouthwash around your mouth for about 1 minute. Spit out the mouthwash, do not swallow it.
Wait at least 30 minutes before having something to eat or drink.
Dosage and how to use throat spray
The throat spray contains a combination of chlorhexidine and lidocaine.
Follow the instructions that come with the medicine packet.
How to use dental treatments
You'll usually use dental treatments once or twice a day.
If you're using dental gel, how you use it depends on why you need it. Follow the instructions from your doctor, dentist or pharmacist.
You may need to use the gel to brush your teeth or you may need to apply it directly to the affected area of your mouth. If you do this, put a small amount of gel onto your fingertip or a cotton bud. Gently wipe it across the surface of your mouth ulcer, your gum or the sore part of your mouth.
Wait at least 30 minutes before having something to eat or drink.
View the original NHS website page ↗. Refreshed 19 August 2026.
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