Metronidazole

These indications are based on manufacturer information for both originator and generic products. For product specific registered indications, please refer to product specific manufacturer information

Registered South African indications:

• Bacterial vaginosis

Contraindications

• Hypersensitivity to the active ingredient or any of its excipients
• Hypersensitivity to other nitroimidazoles or parabens

Cautions

• Pregnancy
• Breastfeeding
• Severe hepatic impairment
• Unrecognised candidiasis
• History of blood dyscrasias
• Central nervous system diseases 

Forms avail. in SA and covered in this monograph: vaginal gel (V gel)

Infections caused by: Anaerobic organisms

Specific doses based on individual indications

Please note that the dosages below should be used in combination with regional guidelines, taking into account local antibiotic sensitivities

Bacterial vaginosis

• Intravaginal (V gel): 37.5mg (one applicator), dly at night; Treatment duration: 5 days (Manufacturer recommendation)

Not established for use in children

Pregnancy

• Caution; no evidence of risk in studies
• The safety of topically applied metronidazole during pregnancy has not been adequately established. The amount of metronidazole available systemically following topical application is less in comparison to oral doses. After oral administration, metronidazole crosses the placental barrier and enters foetal circulation rapidly. No foetotoxicity was observed after oral metronidazole in either rats or mice. However, oral metronidazole has been shown to be a carcinogen in some rodents this drug should be used during pregnancy only if clearly needed

Breastfeeding

• Caution; not recommended
• After oral administration, metronidazole is excreted in breast milk in concentrations similar to those found in the plasma, Metronidazole blood levels from topical administration are significantly lower than those achieved after oral administration. A decision should be made to discontinue breastfeeding or to discontinue metronidazole, taking into account the importance of the drug to the mother

Renal Impairment

• No dose adjustment recommended

Hepatic Impairment

• Mild to moderate; no dose adjustment recommended  
• Caution; Severe

Elderly

• No dose adjustment recommended

Porphyria Information

• Probably not porphyrinogenic (PNP)

Drugs in Sport

• Permitted - No warnings

Central Nervous System Disorders

• Headache
• Dizzyness
• Insomnia

Gastrointestinal Disorders

• Abdominal cramping
• Abdominal pain
• Nausea and vomitting
• Metallic taste in mouth
• Diarrhoea
• Constipation
• Decreased appetite
• Modification of taste

Genitourinary Disorders

• Vaginal candidiasis
• Vulvovaginal itching/burning/swelling
• Increased pelvic pressure
• Increased vaginal discharge
• Cystitis
• Incontinence

Musculoskeletal Disorders

• Incoordination

Skin and Subcutaneous Tissue Disorders

• Generalised rash/pruritus
• Flushing

Immune, Blood and Lymphatic System Disorders

• Decreased white blood cells
• Increased white blood cells
• Leukopenia

• Alcohol
• Lithium
• Warfarin

None routine

Metronidazole is a prodrug that is reduced to its active form intracellularly by anaerobic bacteria. The reduced form then binds to DNA, inhibiting nucleic acid synthesis and ultimately leading to cell death.

Spectrum of activity: Anaerobic organisms

Gel (per 5g) 37.5mg

• Metrogel V (iNova) originator

Also available in the following forms: Capsule, tablet, suspension, injection, suppository and topical gel.