1. Introduction
Fusidic acid is a topical and systemic antibiotic used to treat bacterial infections caused by Staphylococcus aureus and other susceptible organisms. It works by inhibiting bacterial protein synthesis, thereby halting bacterial growth. It is commonly used in skin infections and as part of combination therapy for systemic infections.
2. Indications
- Topical Use:
- Impetigo.
- Infected dermatitis (e.g., atopic dermatitis with secondary infection).
- Infected wounds or burns.
- Systemic Use (Oral or IV):
- Severe skin and soft tissue infections (e.g., cellulitis, abscesses).
- Osteomyelitis.
- Prosthetic joint infections.
- Endocarditis caused by susceptible organisms (often in combination therapy).
3. Dosage
- Topical Use:
- Apply a thin layer to the affected area 2–3 times daily for 7–10 days.
- Cover with a dressing if necessary for wounds or burns.
- Systemic Use (Adults):
- Oral: 500 mg twice or three times daily.
- Intravenous: 500 mg to 1 g every 8 hours.
- Systemic Use (Children):
- Oral: 20–40 mg/kg/day in 2–3 divided doses.
- Intravenous: 20–50 mg/kg/day in 2–3 divided doses.
4. Administration
- Topical: Apply gently to clean, dry skin. Avoid contact with eyes and mucous membranes.
- Oral: Take with food to reduce gastrointestinal side effects.
- Intravenous: Administer as per hospital protocol.
5. Forms Available
- Cream: 2% fusidic acid.
- Ointment: 2% fusidic acid.
- Tablets: 250 mg, 500 mg.
- Intravenous infusion: 500 mg/10 mL.
6. Side Effects
6.1. Topical Use
- Common:
- Skin irritation (e.g., redness, itching, burning).
- Rare:
- Allergic contact dermatitis.
6.2. Systemic Use
- Common:
- Nausea.
- Vomiting.
- Diarrhoea.
- Rare but Serious:
- Hepatotoxicity (elevated liver enzymes, jaundice).
- Severe allergic reactions (e.g., anaphylaxis).
7. Warnings
- Resistance: Prolonged or repeated use can lead to bacterial resistance.
- Systemic Side Effects: Use cautiously in patients with liver impairment due to the risk of hepatotoxicity.
8. Precautions
- Avoid prolonged use of topical formulations to prevent sensitisation and resistance.
- Use systemic formulations cautiously in patients with pre-existing liver disease.
- Monitor for gastrointestinal side effects and liver function during systemic use.
9. Interactions
- Drug-Drug Interactions:
- Statins: Increased risk of rhabdomyolysis when used together.
- Oral anticoagulants (e.g., warfarin): May increase anticoagulant effect; monitor INR closely.
- Cyclosporine: May increase cyclosporine levels, increasing toxicity risk.
10. Monitoring Parameters
- For systemic use:
- Liver function tests during prolonged therapy.
- Clinical improvement in infection symptoms.
- For topical use:
- Signs of irritation or allergic reactions.
11. Use in Children
- Safe for use in children, with doses adjusted based on weight for systemic therapy.
12. Use in Pregnancy
- Category C: Topical use is generally considered safe. For systemic use, weigh the benefits against potential risks.
13. Use in Elderly
- Safe for elderly patients; monitor liver function during systemic use due to potential hepatic sensitivity.
14. Use in Kidney Disease
- No dose adjustment is typically required for topical use. Systemic use requires caution and monitoring in severe renal impairment.
15. Use in Liver Disease
- Use cautiously in patients with liver impairment, as fusidic acid is metabolised in the liver. Monitor liver function during systemic therapy.
16. Patient Counselling Points
- For topical use, apply the cream/ointment as directed and avoid overuse.
- Wash hands before and after applying the cream, unless the hands are the treatment site.
- Do not use topical fusidic acid for longer than 7–10 days unless directed by your doctor.
- For systemic use, take tablets with food to reduce stomach upset.
- Report any symptoms of liver problems, such as yellowing of the skin or eyes.
- Inform your doctor if you are taking statins, anticoagulants, or other medications.
17. Table of Brand Names, Manufacturers, and Prices
Brand Name | Manufacturer | Price (USD) |
---|---|---|
Fucidin (Cream/Ointment) | LEO Pharma | $10–20 (15 g, 2%) |
Fucidin Tablets | LEO Pharma | $50–70 (30 tablets, 500 mg) |
Generic Fusidic Acid | Various manufacturers | $5–15 (15 g, 2%) |
18. FAQs (15 Questions)
- What is fusidic acid used for?
Fusidic acid is used to treat bacterial skin infections like impetigo, infected dermatitis, and infected wounds. Systemically, it treats severe infections like osteomyelitis. - How does fusidic acid work?
It inhibits bacterial protein synthesis, stopping bacterial growth. - How long should fusidic acid be used?
Topical formulations are usually used for 7–10 days. Systemic treatment duration depends on the severity of the infection. - Can fusidic acid cause side effects?
Yes, common side effects include skin irritation (topical use) and nausea or diarrhoea (systemic use). - Can fusidic acid treat fungal infections?
No, it is effective only against bacterial infections. - Is fusidic acid safe during pregnancy?
Topical use is generally safe. Systemic use should only be considered if the benefits outweigh the risks. - Can fusidic acid cause liver problems?
Yes, systemic use can cause hepatotoxicity in rare cases. Monitor liver function during prolonged therapy. - Can fusidic acid be used in children?
Yes, it is safe for children with appropriate dosing adjustments for systemic use. - How should fusidic acid cream be applied?
Apply a thin layer to the affected area 2–3 times daily, avoiding eyes and mucous membranes. - Does fusidic acid interact with other medications?
Yes, it interacts with statins, anticoagulants, and cyclosporine. - Can fusidic acid be used on open wounds?
Yes, it can be applied to clean open wounds unless otherwise advised. - Can fusidic acid treat acne?
It is occasionally used for infected acne lesions but not as a first-line treatment. - Can fusidic acid be used long-term?
Long-term use is not recommended due to the risk of resistance and sensitisation. - What should I do if I miss a dose of fusidic acid?
Apply or take it as soon as you remember, but skip it if it’s close to the next dose. Do not double up. - How should fusidic acid be stored?
Store at room temperature, away from moisture and heat.