This NHS content is written for people in England. Medicine names, availability, prescribing and services may differ in other countries.
Dosage and how to take clarithromycin
Dosage and strength
Clarithromycin tablets come in strengths of 250mg or 500mg. The liquid comes in strengths of 125mg in 5ml or 250mg in 5ml.
The usual dose of clarithromycin is 250mg to 500mg twice a day, although the dose may be lower for children.
If your doctor prescribes slow-release tablets, the usual dose is 500mg once a day. Sometimes a higher dose of 1g once a day is used in severe infections.
These tablets release the medicine slowly through the day, which means you only usually need to take 1 tablet. If you need 2 slow-release tablets a day and have any questions, talk to your doctor or pharmacist and read the instructions carefully.
How to take it
Clarithromycin comes in different forms and strengths, and there are different ways to take it.
Try to take your medicine at the same time every day.
How to take tablets
Swallow the tablets whole with a drink of water. Do not chew or break them. You can take them with or without food.
How to take liquid
Liquid clarithromycin may be made up for you or your child by a pharmacist. Sometimes, you may be given a powder you add water to so you can make the liquid yourself. Follow the instructions in your medicine to do this.
The liquid comes with a plastic syringe or spoon to help you measure the right dose. If you do not have a syringe or spoon, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount.
Shake the liquid well before use.
Try eating or drinking something straight after taking it, to help avoid any bitter aftertaste.
View the original NHS website page ↗. Refreshed 19 August 2026.
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