Name: Cephalexin (Keflex)
Class: First Gen. Cephalosporin
Mech.: Binds to PBPs, blocks activity of transpeptidases in terminal stages of cell wall formation. Bactericidal.
Absorption: Oral.
Distribution: Poor CSF.
Metab.:
Excretion, t½:
Toxicity/S.E.s: Hypersensitivity (some cross-sensitivity to pen.), superinfection, renal damage (worse if comb. w/aminoglycs.)
Utility: Usu not DOC. Serious Klebsiella infects., strep/staph infects, some penicillinase-producing bacteria.
Special Features: Narrow spectrum. Greater gram - activity than pen. G. More gram+ activity than gram - activity. Less susceptible to b-lactamase than most penicillins.