Minimum Inhibitory
Concentrations
(mcg/mL)
Disk Diffusion
(zone diameter in mm)
Pathogen S I R S I R
Enterobacterales ≤ 8 - ≥ 16 - - -
Other non-Enterobacterales ≤ 8 - ≥ 16 - - -
Anaerobes ≤ 8 - ≥ 16 - - -

S = Susceptible; I = Intermediate; R = Resistant
Susceptibility interpretive criteria are based on a dose of 3 g every 6 hours or 4 g every 8 hours in patients with normal renal function.