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Facts about the skin from DermNet New Zealand Trust. Topic index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Metronidazole

Metronidazole is an imidazole antibiotic that is used in the treatment of many protozoal and bacterial infections. It is available in various forms and strengths, including tablets, suspensions, solutions for injections, suppositories and topical creams and gels.

For skin conditions, topical metronidazole is indicated for the treatment of facial rosacea. In New Zealand topical metronidazole is a prescription medicine and is available as a 7.5 mg/g aqueous gel and cream. The brand name of these preparations is Rozex®.

A vaginal gel preparation of metronidazole is also available to treat bacterial vaginosis.

How does metronidazole work?

Metronidazole is an antiprotozoal and anaerobic antibacterial agent. When administered systemically via oral tablets or injection, metronidazole works by inhibiting bacterial DNA synthesis hence preventing the replication of bacteria. However the mechanisms by which topical metronidazole works in reducing inflammatory lesions of rosacea are unknown. Possible mechanisms of action include antibacterial and/or anti-inflammatory effects.

What is topical metronidazole used for?

Topical metronidazole is indicated for the treatment of inflammatory papules, pustules and erythema of rosacea. It should be applied twice daily, morning and evening, to the affected area after washing with a mild cleanser and patting dry. The average period of treatment is 3-4 months, although some improvement should be noticeable after 3 weeks of continued therapy. If significant improvement is seen after 3-4 months, your doctor may prescribe a further 3-4 months therapy. Treatment should be stopped if no clear clinical improvement is evident after the first 3-4 months.

Precautions

Side effects of topical metronidazole

Side effects from the use of topical metronidazole are rare and usually mild. Side effects that should be reported to your doctor as soon as possible include:

Other possible side effects that should resolve after continued use of topical metronidazole include:

Related information

References:

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Author: Vanessa Ngan, staff writer

Note:

The New Zealand approved datasheet is the official source of information for this prescription medicine, including approved uses and risk information. Check the New Zealand datasheet on the Medsafe website.

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If you have any concerns with your skin or its treatment, see a dermatologist for advice.