Precautions
There is evidence to suggest that the drug can penetrate the placental barrier and is detectable in the milk of nursing mothers. Safety of fusidic acid for the treatment of infections in women who are breast-feeding has not been established.
Safety 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 tube contains: fusidic acid 2% in a cream base. Nonmedicinal ingredients: α-tocopherol, butylhydroxyanisole, cetanol, glycerin 85%, paraffin liquid, paraffin white soft, polysorbate 60, potassium sorbate, purified water. Tubes of 15 and 30 g. Store between 15 and 25°C.
Each tube contains: sodium fusidate 2% in an ointment base containing lanolin. Nonmedicinal ingredients: α-tocopherol, cetanol, lanolin anhydrous, liquid paraffin, white soft paraffin. Tubes of 15 and 30 g. Store between 15 and 30°C.
Pharmacology
Fusidic acid inhibits bacterial protein synthesis by interfering with amino acid transfer from aminoacyl-tRNA to protein on the ribosomes. Fusidic acid may be bacteriostatic or bactericidal depending on inoculum size. Although bacterial cells stop dividing almost within 2 minutes after contact with the antibiotic in vitro, DNA and RNA synthesis continue for 45 minutes and 1 to 2 hours, respectively.
Fusidic acid is virtually inactive against gram-negative bacteria. The differences in activity against gram-negative and gram-positive organisms are believed to be due to a difference in cell wall permeability.
Mammalian cells are much less susceptible to inhibition of protein synthesis by fusidic acid than sensitive bacterial cells. These differences are believed to be due primarily to a difference in cell wall permeability.
Contraindications
Sensitivity to fusidic acid and its salts, or lanolin in respect of Fucidin ointment.
Adverse Effects
Mild irritation has occasionally been reported in patients with dermatoses treated with fusidic acid. It was not usually necessary to discontinue therapy. The application of fusidic acid to deep leg ulcers has been associated with pain. Reports of hypersensitivity reactions have been rare.
Indications
The treatment of primary and secondary skin infections caused by sensitive strains of S. aureus, Streptococcus species and C. minutissimum. Primary skin infections that may be expected to respond to treatment with fusidic acid topical include: impetigo contagiosa, erythrasma and secondary skin infections such as infected wounds and infected burns.
Appropriate culture and susceptibility studies should be performed. However, while waiting results of these studies and, if antibiotic therapy is considered to be necessary, fusidic acid topical may be administered to those patients in whom an infection caused by susceptible bacteria is suspected. This antibiotic treatment may subsequently require modification once these results become available.
In addition, local concentrations of fusidic acid topical are active against other Corynebacteria, Neisseria, Clostridia and Bacteroides species. No cross-resistance has been observed to date between Fucidin and other antibiotics presently in clinical use.
Resistance to fusidic acid has readily been induced in vitro. The development of resistance has also been shown to occur in the clinical setting.
Dosage
Ointment and Cream: Apply a small amount to the lesion 3 or 4 times daily until favorable results are achieved. Whenever the lesion is to be covered with a gauze dressing, less frequent applications (1 or 2 daily) may be used. In impetigo contagiosa, it has not been shown necessary to remove the crusts before application.
When treating the face, care should be taken to avoid the eye.
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 fusidic acid ointment or cream.
