Usage
Sodium Fusidate is a narrow-spectrum antibiotic primarily effective against Staphylococcus aureus infections. It is prescribed for various staphylococcal infections, including skin and soft tissue infections (such as impetigo, boils, and abscesses), bone infections (osteomyelitis), respiratory infections (pneumonia), bloodstream infections (septicemia), endocarditis, and superinfected cystic fibrosis. Its pharmacological classification is antibiotic.
Sodium Fusidate’s mechanism of action involves inhibiting bacterial protein synthesis by binding to elongation factor G (EF-G), preventing its translocation on the ribosome. This disrupts the movement of tRNA and mRNA during translation, effectively halting protein synthesis and leading to bacterial growth inhibition.
Alternate Names
Sodium Fusidate is also known as fusidic acid sodium. Popular brand names include Fucidin, Fucithalmic (for eye preparations), and Fucibet (in combination with betamethasone).
How It Works
Pharmacodynamics: Sodium Fusidate exerts its bactericidal effect primarily against Staphylococcus aureus, including methicillin-resistant strains. It has limited activity against other gram-positive bacteria and some gram-negative organisms.
Pharmacokinetics:
- Absorption: Oral absorption of sodium fusidate tablets is high (around 90%), but variable. Absorption can be reduced if taken with food. Suspension formulations have lower bioavailability.
- Distribution: Sodium Fusidate is widely distributed in the body, achieving therapeutic concentrations in bone, synovial fluid, and other tissues. It is highly protein-bound (over 90%).
- Metabolism: It is metabolized in the liver.
- Elimination: Excretion occurs primarily via the biliary route with minimal renal elimination. This makes dose adjustments unnecessary in patients with renal impairment.
Mode of Action: Sodium Fusidate binds to EF-G, preventing its translocation along the ribosome during bacterial protein synthesis. This action inhibits the formation of peptide bonds, halting the growth and replication of the bacteria.
Receptor binding, enzyme inhibition, or neurotransmitter modulation: The main mechanism involves inhibiting EF-G, a key component of the bacterial protein synthesis machinery. It can also inhibit chloramphenicol acetyltransferase enzymes.
Elimination pathways: Primarily biliary excretion, with minimal renal elimination.
Dosage
Standard Dosage
Adults:
- Tablets:
- Skin infections: 250 mg twice daily for 5-10 days.
- Other infections: 500 mg three times daily. The dose may be doubled in severe infections.
- Suspension: 750 mg (15 ml) three times daily.
Children:
- Suspension:
- Infants (up to 1 year): 50 mg/kg/day divided into three doses.
- 1-5 years: 250 mg (5 ml) three times daily.
- 5-12 years: 500 mg (10 ml) three times daily.
- Tablets: Over 12 years: same as adult dose.
Special Cases:
- Elderly Patients: No dose adjustment is generally necessary.
- Patients with Renal Impairment: No dose adjustment is required.
- Patients with Hepatic Dysfunction: Dose reduction may be necessary due to hepatic metabolism.
- Patients with Comorbid Conditions: Use with caution in patients with biliary disease. Co-administration with statins is contraindicated.
Clinical Use Cases
Dosage recommendations for specific clinical situations (Intubation, Surgical Procedures, Mechanical Ventilation, ICU Use, Emergency Situations) are not explicitly defined in the provided information but general dosage guidance applies. In severe infections, higher doses or combination therapy may be indicated.
Dosage Adjustments
Dose adjustments may be required in patients with hepatic impairment. No adjustments are necessary for renal dysfunction.
Side Effects
Common Side Effects
Gastrointestinal disturbances (nausea, vomiting, diarrhea, abdominal pain, dyspepsia), skin rashes, itching.
Rare but Serious Side Effects
Jaundice (including cholestatic jaundice), hepatitis, blood disorders (leukopenia, thrombocytopenia, anemia), hypersensitivity reactions, angioedema, serious skin reactions (DRESS syndrome, Stevens-Johnson syndrome, toxic epidermal necrolysis), rhabdomyolysis (especially with statins), acute renal failure.
Long-Term Effects
Potential for antibiotic resistance with prolonged or repeated use.
Adverse Drug Reactions (ADR)
The aforementioned serious side effects require immediate intervention.
Contraindications
Hypersensitivity to sodium fusidate or any of its components. Concomitant use with statins.
Drug Interactions
Clinically significant interactions include statins (increased risk of rhabdomyolysis), some HIV protease inhibitors (ritonavir, saquinavir, fosamprenavir, nelfinavir - increased sodium fusidate levels), and some blood thinners.
Pregnancy and Breastfeeding
Limited data are available on use during pregnancy. Systemic use should be avoided if possible, especially during the first trimester. Topical use is generally considered safe. Fusidic acid is excreted in breast milk; however, topical application poses minimal risk to infants.
Drug Profile Summary
- Mechanism of Action: Inhibits bacterial protein synthesis by binding to EF-G, blocking translocation on ribosomes.
- Side Effects: Nausea, vomiting, diarrhea, skin rashes, jaundice (rare), blood disorders (rare), serious skin reactions (rare), rhabdomyolysis (with statins).
- Contraindications: Hypersensitivity, concomitant use with statins.
- Drug Interactions: Statins, some HIV protease inhibitors, some anticoagulants.
- Pregnancy & Breastfeeding: Avoid systemic use if possible during pregnancy. Topical use is generally considered safe. Excreted in breast milk, minimal risk with topical use.
- Dosage: Adults: 250mg twice daily (skin); 500mg three times daily (other). Children (suspension): dose varies by age/weight.
- Monitoring Parameters: Liver function tests (especially with high doses or prolonged treatment).
Popular Combinations
Often combined with other antibiotics (e.g., penicillinase-resistant penicillins) for synergistic effects in serious infections or to broaden the spectrum of activity.
Precautions
- General Precautions: Monitor liver function, especially with high doses or prolonged use. Screen for pre-existing liver/biliary disease.
- Specific Populations: Use with caution in neonates due to the risk of kernicterus. Avoid use in patients with a history of hypersensitivity. Close monitoring required when used in individuals with hepatic impairment.
- Lifestyle Considerations: No specific lifestyle considerations, other than avoiding alcohol while taking any medication if possible.
FAQs (Frequently Asked Questions)
Q1: What is the recommended dosage for Sodium Fusidate?
A: Adults: 250 mg twice daily for skin infections; 500 mg three times daily for other infections. Pediatric dosing is weight/age-dependent and should be based on the suspension formulation.
Q2: What infections is Sodium Fusidate used to treat?
A: Primarily Staphylococcus aureus infections, including skin infections, osteomyelitis, pneumonia, septicemia, and endocarditis.
Q3: What is the mechanism of action of Sodium Fusidate?
A: Inhibits bacterial protein synthesis by binding to elongation factor G (EF-G) on the ribosome, preventing translocation.
Q4: Can Sodium Fusidate be used in pregnant or breastfeeding women?
A: Systemic use should generally be avoided if possible, especially during the first trimester. Topical use is generally considered safe. Excretion into breast milk is minimal with topical use.
Q5: What are the common side effects of Sodium Fusidate?
A: Gastrointestinal disturbances (nausea, vomiting, diarrhea) and skin rashes.
Q6: What are the serious side effects of Sodium Fusidate?
A: Jaundice, hepatitis, blood disorders, hypersensitivity reactions, severe skin reactions (DRESS, SJS, TEN), and rhabdomyolysis (especially with concomitant statin use).
Q7: What are the major drug interactions with Sodium Fusidate?
A: Statins (increased risk of rhabdomyolysis), certain HIV protease inhibitors (increased sodium fusidate levels), and some blood thinners/anticoagulants.
Q8: What is the importance of avoiding concomitant use of statins with Sodium Fusidate?
A: Concurrent use significantly increases the risk of rhabdomyolysis, a potentially life-threatening condition.
Q9: Are there any dosage adjustments needed for patients with renal impairment?
A: No, because Sodium Fusidate is primarily excreted in bile.
Q10: What are the key monitoring parameters during Sodium Fusidate therapy?
A: Monitoring of liver function is important, especially for prolonged therapy or high doses.
