Azithromycin, Clarithromycin and Erythromycin belong to a group of medicines used to prevent or treat bacterial infections known as macrolides.

​What is this medication used for?

Macrolides are antibiotics used to prevent or treat infections caused by certain bacteria. These may include infections of the lung, skin and soft tissue.

Dosage and How to Use​​​

You should complete each course of antibiotics even if you feel better as incomplete treatment might cause the infection to return or cause antibiotic resistance. When antibiotic resistance happens, the antibiotic will not be able to control the growth or kill the bacteria anymore.

Refer to the following table to find out when to take your medicine:


When to Take

Azithromycin, Clarithromycin

With or after food

Erythromycin Suspension

With or after food

Erythromycin Tablets

Half to one hour before food. If you develop stomach upset, take it with or after food.

If you miss a dose, take the missed dose as soon as you remember. If it is almost time for your next dose, take only the usual dose. Do not double your dose or use extra medicine to make up for the missed dose.

Side Effects, Precautions, Contraindication​​

What are the possible side effects of the medicines?​​​​

The common side effects of these medicines include:

  • ​Nausea or vomiting

  • Stomach discomfort

  • Diarrhoea

If you experience any of the following rare but serious side effects, you should stop the medicine and see a doctor immediately.

  • Serious diarrhoea that does not stop, is very loose or watery and you have blood in your stools together with stomach pain or cramps

  • ​Abnormal heartbeats

How do I know if I am allergic to these medicines?

The symptoms of a drug allergy include one or more of the following:

  • Swollen face/eyes/lips

  • Difficulty in breathing

  • ​​Itchy skin rashes over your whole body

If you experience any of these symptoms, you should stop your medicine immediately and see your doctor.

What precautions should I follow when taking the medicines?

Before starting on these medicines, inform your doctor or pharmacist if:

  • You had an allergic reaction before to azithromycin, clarithromycin, erythromycin or other macrolide antibiotics.

  • Your doctor told you that you have slow heartbeats.

  • You are taking medicines to treat abnormal heartbeats.

  • You are taking anticoagulants to thin your blood (e.g. warfarin).

  • You are taking ergotamine, a medicine to treat migraines.

  • ​You are taking statins, which are medicines used to treat high blood cholesterol.

Macrolides can affect the levels of other medicines in your body. Do let your doctor or pharmacist know what other medicines, including over-the-counter medicines, vitamins and herbal products you are taking before starting on your antibiotic.

Handling and Storage​​

  • Keep your medicines in the original container or packaging, tightly closed or sealed in a cool and dry place, away from direct sunlight.

  • Keep the medicine out of reach of children.

  • Throw away all expired medicines.

This article​ answers some common questions about this medicine. It does not contain all the available information. It also does not take the place of talking to your doctor or pharmacist.



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