Pharmacology
Mupirocin exerts a bactericidal action against sensitive organisms by inhibiting bacterial protein synthesis. It reversibly and specifically binds to bacterial isoleucyl transfer-RNA synthetase.
Indications
For the topical treatment of the following, when caused by sensitive strains of staphylococcus and streptococcus species: impetigo, superficially infected dermatoses, lesions which are moist and weeping.
For abrasions, minor cuts and wounds, the use of mupirocin may prevent the development of infections by sensitive Gram-positive organisms.
No cross-resistance has been shown between mupirocin and other commonly used antibiotics.
Precautions
Caution should be exercised when mupirocin ointment is administered to nursing mothers. If a cracked nipple is to be treated, lactation from the affected breast should be maintained by manual expression until the end of treatment. During this time, milk from the affected breast should be discarded.
The safety of mupirocin ointment in the treatment of infections during pregnancy has not been established. If administration to pregnant patients is considered necessary, its potential benefits should be weighed against the possible hazards to the fetus.
Supplied
Each g of ointment contains: mupirocin 20 mg (2%) in a bland water-soluble ointment base consisting of polyethylene glycol 400 and polyethylene glycol 3350 (polyethylene glycol ointment, USP). Tubes of 15 and 30 g. Store at room temperature.
Contraindications
In patients with hypersensitivity to mupirocin or to other ointments containing polyethylene glycols.
Warnings
This mupirocin ointment formulation is not suitable for ophthalmic or intranasal use, or in conjunction with cannulae.
When mupirocin ointment is used on the face, care should be taken to avoid the eyes.
Polyethylene glycol (PEG) can be absorbed from open wounds and damaged skin. It is excreted by the kidneys. As with other PEG-based ointments, mupirocin ointment should not be used in conditions where absorption of large quantities of PEG is possible, especially if there is evidence of moderate or severe renal impairment.
In the rare event of a possible sensitization reaction or severe local irritation occurring with the use of mupirocin, treatment should be discontinued and appropriate alternative therapy for the infection instituted.
Adverse Effects
The following local adverse reactions have been reported during therapy with mupirocin: itching, burning, erythema, stinging and dryness. It was not usually necessary to discontinue therapy due to these adverse reactions. Systemic allergic reactions have been reported with mupirocin ointment. Cutaneous sensitization reactions to mupirocin or the ointment base have been reported rarely.
Overdose
For management of a suspected drug overdose, CPhA recommends that you contact your regional Poison Control Centre. See the eCPS Directories section for a list of Poison Control Centres.
Overdosage has not been known to occur during topical therapy with mupirocin ointment.
Dosage
A small amount of the ointment should be applied to the affected area 3 times daily for up to 10 days, depending on the response. The area treated may be covered with a gauze dressing if desired.
