Written by the Fiveable Content Team • Last updated September 2025
Written by the Fiveable Content Team • Last updated September 2025
Definition
Oxacillin is a beta-lactam antibiotic used to treat infections caused by penicillinase-producing staphylococci. It is resistant to degradation by beta-lactamase enzymes.
5 Must Know Facts For Your Next Test
Oxacillin is effective against Staphylococcus aureus, including methicillin-sensitive strains (MSSA).
It is administered intravenously or intramuscularly due to poor oral absorption.
Oxacillin works by inhibiting bacterial cell wall synthesis, leading to cell lysis and death.
The drug is often used in clinical settings for bloodstream infections, endocarditis, and other serious conditions caused by staphylococci.
Resistance to oxacillin indicates methicillin-resistant Staphylococcus aureus (MRSA), requiring alternative treatments.
A common bacterium that can cause various infections; some strains produce penicillinase.
Beta-lactamase: An enzyme produced by certain bacteria that degrades beta-lactam antibiotics.
Methicillin-resistant Staphylococcus aureus (MRSA): A strain of Staphylococcus aureus resistant to methicillin and related antibiotics, often requiring alternative treatments.