Antibiotic	Half-life (hours)
Cefazolin (Ancef, Kefzol)	1.8
Vancomycin (Vancocin)	3 to 9
Cefoxitin (Mefoxin)	0.6 to 1
Cefotetan (Cefotan)	3 to 4.6
Aminoglycosides	2
Metronidazole (Flagyl)	8
Clindamycin (Cleocin)	2.4 to 3
Ciprofloxacin (Cipro)	3 to 5