What is flucloxacillin?

Flucloxacillin

Flucloxacillin is a narrow-spectrum antibiotic of the penicillin class. It is primarily used to treat infections caused by susceptible Gram-positive bacteria, particularly Staphylococcus aureus, including strains that are resistant to penicillin (but not methicillin-resistant Staphylococcus aureus, MRSA).

• Mechanism of Action: Flucloxacillin inhibits bacterial cell wall synthesis by binding to penicillin-binding proteins (PBPs). This prevents the cross-linking of peptidoglycans, which are essential components of the bacterial cell wall, ultimately leading to bacterial cell death. You can check Mechanism%20of%20Action for more information.

• Indications: Common uses include:

  • Skin and soft tissue infections (e.g., cellulitis, impetigo, boils)
  • Bone and joint infections (e.g., osteomyelitis, septic arthritis)
  • Pneumonia (in some cases)
  • Endocarditis (in some cases, usually in combination with other antibiotics)

• Administration: It is available in oral (capsules or solution) and intravenous formulations. Oral formulations should be taken on an empty stomach, at least 30 minutes before food.

• Adverse Effects: Common side effects can include:

  • Gastrointestinal disturbances (nausea, vomiting, diarrhea)
  • Skin rash
  • Injection site reactions (with IV administration)

  Serious but less common side effects can include:

  • Allergic reactions (including anaphylaxis)
  • Liver problems (e.g., cholestatic jaundice, hepatitis). You can check Liver%20problems for more information.
  • Clostridium difficile-associated diarrhea (CDAD)

• Contraindications and Precautions:

  • Hypersensitivity to penicillins or cephalosporins. You can check Hypersensitivity for more information.
  • History of flucloxacillin-associated jaundice or hepatic dysfunction.
  • Caution is advised in patients with impaired liver function or renal impairment.
  • Use with caution in the elderly.

• Drug Interactions: Flucloxacillin can interact with other medications, including:

  • Warfarin (may increase the risk of bleeding). You can check Warfarin for more information.
  • Methotrexate (may increase methotrexate toxicity)
  • Probenecid (may increase flucloxacillin levels)

• Pregnancy and Breastfeeding: Flucloxacillin can be used during pregnancy and breastfeeding, but caution is advised and a healthcare professional should be consulted.