Metrotop.

Metronidazole BP 0.8% w/v.

A colourless aqueous gel.

For the treatment of malodorous fungating tumours, gravitational ulcers and decubitus ulcers (pressure sores).

For external use only. Adults: All wounds should be cleaned thoroughly. Flat wounds require a liberal application of the gel over the complete area. Cavities should be loosely packed with paraffin gauze which has been smeared in the gel. All wounds should be covered with a non-adherent dressing and a pad of lint or gauze. Sticking may occur if the appropriate dressing is not used. Use once or twice daily as necessary. Elderly: No specific instructions. Children: Where necessary, instructions apply as for adults.

Known hypersensitivity to metronidazole.

The following statements take into account the possibility that metronidazole may be absorbed after topical application. However, there is no evidence of any significant systemic concentrations of metronidazole following topical applications. Peripheral neuropathy has been reported in association with prolonged use of metronidazole. The elimination half-life of metronidazole remains unchanged in the presence of renal failure. Such patients, however, retain the metabolite of metronidazole. The clinical significance of this is not known at present. However, in patients undergoing dialysis, metronidazole and metabolites are efficiently removed.

Some potentiation of anticoagulant therapy has been reported when metronidazole has been used with the warfarin type oral anticoagulants. Patients receiving phenobarbitone metabolise metronidazole at a much faster rate than normal, reducing the half-life to approximately 3 hours. Patients are advised not to take alcohol during systemic metronidazole therapy because of the possibility of a disulfiram-like reaction.

There is inadequate evidence of the use of metronidazole in pregnancy. Metronidazole gel cannot therefore be recommended during pregnancy or lactation where significant systemic absorption may occur unless the physician considers it essential.

None known.

No adverse effects have been reported. Systemic metronidazole therapy may occasionally cause an unpleasant taste in the mouth, furred tongue, nausea, vomiting, gastrointestinal disturbance, urticaria, angioedema and anaphylaxis. Drowsiness, dizziness, headache, ataxia, skin rash, pruritus, and darkening of the urine have been reported, but rarely.

There is no specific treatment for gross overdosage of metronidazole. Gastric lavage is recommended in cases of accidental ingestion. Uneventful recovery has followed overdosage of up to 12g taken orally. Metronidazole is readily removed from the plasma by dialysis.

Metronidazole is a potent agent against the anaerobic bacteria which are believed to produce odorous metabolites as a result of localised tissue colonisation. The aim of the product is to provide a high concentration of metronidazole at and around the site of colonisation in a water-miscible base. This form allows surface spread and penetration within the wound accompanied by ease of aseptic application and up to 24 hours duration of action.

There is presently no evidence of any systemic concentrations of metronidazole following topical application.

No further data given.

Hypromellose (4500); benzalkonium chloride solution; purified water.

None known.

The shelf life shall not exceed 24 months from the date of manufacture.

Do not store above 25°C. Once opened the contents should be used within 28 days of opening.

Polypropylene tubes each fitted with a plastic screw cap and tamper-evident seal and enclosed within a printed cardboard carton. Single tubes may sometimes be supplied without a carton. Pack sizes: The 15g, 30g and 60g tubes are available singly or in boxes of 12.

None given.

Medlock Medical Limited, Tubiton House, Medlock Street, Oldham, OL1 3HS.

PL 21248/0040.

16^th September 2005.

September 2005.