Oxacillin nephritis

Acute interstitial nephritis secondary to administration of antibiotics is a well-described entity. Oxacillin, however, has never been directly implicated. An 80-year-old man had a rising creatinine level and eosinophiluria while receiving oxacillin sodium. These findings disappeared when use of the drug was discontinued. We conclude that oxacillin is an additional penicillin that can cause interstitial nephritis.