🦠microbiology review

Nafcillin

Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025

Definition

Nafcillin is a beta-lactam antibiotic belonging to the penicillin class, primarily used for treating infections caused by penicillinase-producing staphylococci. It is commonly administered intravenously due to its poor absorption when taken orally.

Pep mascot

5 Must Know Facts For Your Next Test

  1. Nafcillin is effective against Staphylococcus aureus strains that produce beta-lactamase, an enzyme that deactivates many other penicillins.
  2. It is often used for serious bacterial infections such as endocarditis, osteomyelitis, and septicemia.
  3. Nafcillin works by inhibiting the synthesis of bacterial cell walls, leading to cell lysis and death.
  4. Unlike many other antibiotics, nafcillin does not require dosage adjustment in patients with renal impairment.
  5. Common side effects include hypersensitivity reactions, gastrointestinal disturbances, and potential liver function abnormalities.

Review Questions