Authors: DermNet Editorial Board, 2001.

What is erythromycin?

Erythromycin is a macrolide antibiotic. Other macrolide antibiotics include azithromycin, clarithromycin, roxithromycin.

What is erythromycin used for?

Erythromycin is prescribed by dermatologists for a variety of skin conditions including:

Erythromycin is particularly useful in individuals allergic to penicillin and in children that are too young for a tetracycline.

It is active against many gram-positive organisms (including Staphylococcus aureus, Streptococcus pyogenes, corynebacteria and clostridia) and some gram-negative organisms (Neisseria gonorrhoeae,). It is also effective for mycoplasma infections, syphilis and chlamydia.

Unfortunately, increasing resistance is being reported.  The prolonged use of erythromycin has been questioned in dermatology, because it can lead to bacterial resistance to the pathogenStaphylococcus aureus (see MRSA), as well as resistance to acne bacteria (C acnes).

How is erythromycin taken?

Oral erythromycin is best taken fasting or just before meals. It comes in a number of bases and formulations.

It is available in New Zealand as the base compound:

The estolate salt is:

The ethyl succinate salt is:

The stearate salt is:

In addition, it is available as a topical preparation for acne (Eryacne gel, Stiemycin solution). A non-antibiotic product such as benzoyl peroxide or a topical retinoid should also be applied, to reduce antibiotic resistance.

Side effects of erythromycin

Erythromycin is generally well tolerated. It is thought that it can be used safely in pregnancy and during breast feeding.

The following side effects are uncommon.

Drug interactions with erythromycin

Erythromycin has important interactions with other medications. Tell your doctor the names of all medications you are taking, whether prescribed or purchased without prescription.

Erythromycin can increase the concentration of the following medications resulting in potentially toxic levels:

New Zealand approved datasheets are the official source of information for these prescription medicines, including approved uses and risk information. Check the individual New Zealand datasheet on the Medsafe website.

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