Antimicrobials are used to treat infected eczema. Find out how long should I use them for

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Why are they used?

The bacteriaStaphylococcus aureus can be found on most people's skin. However, on skin that is affected by atopic eczema, increased numbers of these bacteria are found in over 90 per cent of cases.



Controlling the number of these bacteria on the skin can help control the eczema.

Skin affected by eczema also has fewer defences against bacteria, viruses and fungi than healthy skin, which can allow the numbers of micro-organisms on the skin to increase.

This predisposes the skin to infection and is why scratching and breaking the skin can often cause it to become infected. Infection subsequently increases the inflammation.

Antimicrobials are used to treat infected eczema.

Antimicrobials are also included in some topical corticosteroid products that are prescribed with the aim of helping to prevent infection, for example in moist areas of skin where infection is more likely, such as nappy rash, seborrhoeic dermatitis, or inflamed areas where skin surfaces are in contact (intertrigo), eg between the thighs or between the buttocks.

However, combined corticosteroid-antibiotic products generally have no advantage over the corticosteroid alone, unless the eczema is actually infected.

They may also increase the risk of skin sensitisation and encourage the growth of bacteria that are resistant to the antibiotic.

How do I know if my eczema is infected?

You should suspect that your eczema is infected if it is crusting, weeping or producing pus, if the eczema appears to suddenly get worse, or if the surrounding normally healthy skin becomes red, hot and swollen.

If you think your eczema is infected it is important to consult your doctor so that this can be confirmed and the infection treated. In the meantime you should not use calcineurin inhibitors (if normally used), because these can allow the infection to spread.

Sometimes your doctor may want to take a swab from the infected area to identify the organism that is causing the infection, as this will help decide the most appropriate treatment.

What type of antimicrobials might be prescribed?

Localised infections that are not too severe may be treated with an antimicrobial cream, or a cream containing a combination of corticosteroid and antimicrobial.

Topical antibiotics include fusidic acid, neomycin, oxytetracyclin and mupirocin. Topical antifungals include nystatin and econazole.

Moderate to more severe extensive infections may require treatment by mouth, for example with a course of antibiotic tablets.

The most common oral antibiotics to be prescribed for bacterially infected eczema are flucloxacillin (a type of penicillin) or erythromycin (if allergic to penicillin).

You may also be prescribed a course of these if your eczema is hard to control and skin swabs reveal large numbers of Staphyllococcus aureus on your skin.

If your eczema becomes infected with the cold sore virus (Herpes simplex) your doctor should urgently prescribe a course of aciclovir to be taken as a tablet or syrup. In severe cases, the treatment should be given in hospital via a drip.

Seborrhoeic eczema is associated with the presence of the yeast Malassezia furfur on the skin, and shampoos containing medicines that are active against this yeast, for example ketoconazole shampoo, may be used to treat this type of eczema.

How long should I use them for?


It is important that you finish the course of antimicrobial unless otherwise advised by your doctor, even if it seems the infection has cleared up.


Are there any side-effects?

Topical antimicrobials are unlikely to cause any problems, though some people may occasionally find their skin becomes over-sensitive or allergic to them.

This is more likely if the preparation is used for longer than instructed by your doctor or repeatedly for recurrent infections.

The most common side-effects associated with oral antibiotics, such as flucloxacillin and erythromycin, are stomach upsets such as nausea, vomiting or diarrhoea.

You can get more information about possible side-effects from the patient information leaflet that will be provided with your medicine.

Can I drink alcohol if I am prescribed antibiotics?

It is a common misconception that alcohol should be strictly avoided by people who are taking a course of antibiotics.



What if I'm taking other medicines?

If you are taking a combined oral contraceptive pill and are prescribed a course of oral antibiotics there is a very low risk that the antibiotic may make your pill less effective at preventing pregnancy.

For this reason you should use an additional barrier method of contraception, eg a condom, both during the antibiotic course and for seven days after finishing the antibiotic.

Always tell your doctor or pharmacist what other medicines you are taking, including those bought without a prescription and herbal medicines, when you are prescribed a new medicine.

How can I avoid infections?

  • Don't leave the any of your creams, lotions, etc open, as this makes them more likely to become contaminated with bacteria. For the same reason it may be worthwhile to use a clean spoon to remove creams from tubs or jars. Pump dispensers may also be useful.
  • Always wash your hands before applying creams, etc to the skin.
  • Using bath additives or moisturisers that contain antiseptics can help prevent infection by killing the bacteria found on the skin.
  • Try not to scratch your eczema as this helps micro-organisms to penetrate the skin.
  • Keep your nails short.

    Other people also read:

    Eczema: what is eczema?

    Seborrhoeic dermatitis: what are the symptoms?

    Nappy rash: what can you do about a nappy rash?

    Based on a text by Helen Marshall, pharmacist

    Last updated

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