Metrotop
SUMMARY OF PRODUCT CHARACTERISTICS 1 NAME OF THE MEDICINAL PRODUCT
Metrotop
2 QUALITATIVE AND QUANTITATIVE COMPOSITION
Metronidazole BP 0.8 %w/v
3 PHARMACEUTICAL FORM
A colourless aqueous gel
4 CLINICAL PARTICULARS
4.1 Therapeutic indications
For the treatment of malodorous fungating tumours, gravitational ulcers and decubitus ulcers.
4.2 Posology and method of administration
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.
4.3 Contraindications
Known hypersensitivity to metronidazole.
4.4 Special warnings and precautions for use
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.
4.5 Interaction with other medicinal products and other forms of interaction
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.
4.6 Fertility, Pregnancy and lactation
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.
4.7 Effects on ability to drive and use machines
None known.
4.8 Undesirable effects
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 has been reported, but rarely.
4.9 Overdose
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.
5 PHARMACOLOGICAL PROPERTIES
5.1 Pharmacodynamic properties
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.
5.2 Pharmacokinetic properties
There is presently no evidence of any systemic concentrations of metronidazole following topical application.
5.3 Preclinical safety data
No further data given.
6.1 List of excipients
Hypromellose (4500) Benzalkonium chloride solution Purified water
6.2 Incompatibilities
None known.
6.3 Shelf life
The shelf life shall not exceed 24 months from the date of manufacture.
6.4 Special precautions for storage
Do not store above 25°C.
Once opened the contents should be used within 28 days of opening.
6.5 Nature and contents of container
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. Packs sizes: The 15g, 30g and 60g tubes are available singly or in boxes of 12.
6.6 Special precautions for disposal
None given.
7 MARKETING AUTHORISATION HOLDER
Ayrton Saunders Ltd
9 Arkwright Road
Astmoor Industrial Estate
Runcorn
Cheshire
WA7 1NU
United Kingdom
MARKETING AUTHORISATION NUMBER(S)
PL 16431/0198
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DATE OF FIRST AUTHORISATION/RENEWAL OF THE AUTHORISATION
17/10/2005
DATE OF REVISION OF THE TEXT
22/11/2012
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