Nafcillin toxicity

For parenteral therapy, nafciUin and oxacillin offer comparable efficacy and antimicrobial spectra of activity. Although both drugs undergo hepatic metabolism, only nafcillin requires dose adjustment in patients with combined hepatic and renal insufficiency. Other pharmacokinetic data for nafcillin and oxacillin appear in Table 45.1. Indications for nafcillin or oxacillin include severe staphylococcal infections like cellulitis, empyema, endocarditis, osteomyelitis, pneumonia, septic arthritis, and toxic shock syndrome. 

It is incumbent on health professionals to avoid toxic drugs whenever possible. Antibiotics associated with CNS toxicities, usually when not dose-adjusted for renal function, include penicillins, cephalosporins, quinolones, and imipenem. Hematologic toxicities generally are manifested with prolonged use of nafcillin (neutropenia), piperacillin (platelet dysfunction), cefotetan (hypoprothrombinemia), chloramphenicol (bone marrow suppression, both idiosyncratic and dose-related toxicity), and trimethoprim (megaloblastic anemia). Reversible nephrotoxicity classically is associated with aminoglycosides... 

ApparerU toxic effects include bone marrow depression, granulocytopenia, and hepatitis the latter is rare but is seen most commonly following the administration of oxacillin and nafcillin. Penicillin G, carbenicillin, piperacillin, or ticarcillin has been associated with impaired hemostasis due to defective platelet aggregation. 

Intravenous 50 mg weekly Phenoxymethylpenicillin 250 mg on alternate days Dermatomyositis (also treated with prednisone and prostatic cancer treated with diethylstilbestrol (stilboestrol) also treated with furosemide) Methotrexate toxicity within week of starting phenoxymethylpenicillin treated with folinic acid and fluid replacement (and nafcillin and tobramycin) 9... 

---