Pharm 101: Flucloxacillin

Class

Beta-lactam antibiotic

Pharmacodynamics

• Beta-lactam antibiotic
• Inhibits bacterial growth by binding to active site of penicillin binding proteins (PBP), interfering with transpeptidation of bacterial cell wall synthesis
• This leads to cell death (bactericidal)
• Flucloxacillin is an anti-staphylococcal penicillin, resistant to staphylococcal beta-lactamase

Pharmacokinetics

• Part biliary excretion, therefore no dose adjustment required in renal failure
• Given before meals as is food interferes with absorption
• For other pharmacokinetic properties of penicillins, see Pharm 101: Penicillin G

Antimicrobial activity

• Resistant to staphylococcal beta-lactamases
• Active against Staph and Strep
• Not active against enterococci, gram negative cocci and rods, and anaerobic bacteria

Adverse effects

• Specific to anti-staphylococcal penicillins (rare):
  • Hepatitis
  • Interstitial nephritis
  • Neutropenia

Further reading

• Buttner R. Pharm 101: Penicillin G. LITFL

References

• Katzung BG. Basic and Clinical Pharmacology. 14e. 2018