Name: Methicillin (Staphcillin)
Class: Penicillin (Penicillinase-resistant)
Mech.: Binds to PBPs, blocks activity of transpeptidases in terminal stages of cell wall formation. Bactericidal.
Absorption: Usu. IV for seious infections. IM.
Distribution: Widely distributed, little CSF unless meninges inflamed.
Metab.:
Excretion, t½: Rapidly elim. by kidneys (probenecid blocks excretion), small amt. in bile.
Toxicity/S.E.s: hypersensitivity (1-10%), superinfection.
Utility: Penicillinase-producing staph. infections. Gram +.
Special Features: Narrow spectrum.