Nafcillin-d5 is intended for use as an internal standard for the quantification of nafcillin by GC- or LC-MS. Nafcillin is a semisynthetic and penicillinase-resistant penicillin antibiotic.1 It is active against 20 clinical isolates of S. aureus with minimum bactericidal concentration (MBC) values ranging from 0.078 to 0.312 µg/ml. Nafcillin (100-800 mg/kg) reduces the number of kidney colony forming units (CFUs) in a mouse model of S. aureus infection.2 It also reduces the number of right atrial CFUs in a rabbit model of S. aureus-induced endocarditis.3 Formulations containing nafcillin have been used in the treatment of various bacterial infections.
1.Tuazon, C.U., Lin, M.Y., and Sheagren, J.N.In vitro activity of rifampin alone and in combination with nafcillin and vancomycin against pathogenic strains of Staphylococcus aureusAntimicrob. Agents Chemother.13(5)759-761(1978) 2.Yuchenco, J.A., Hopper, M.W., Vince, T.D., et al.Nafcillin and oxacillin: Comparative antistaphylococcal activity in miceJ. Antibiot. (Tokyo)29(4)460-465(1976) 3.Carrizosa, J., Kobasa, W.D., and Kaye, D.Effectiveness of nafcillin, methicillin, and cephalothin in experimental Staphylococcus aureus endocarditisAntimicrob. Agents Chemother.15(5)735-737(1979)