Antibiotic | Disc potency (µg) | Inhibition zone diameter (mm) | ||
---|---|---|---|---|
R | I | S | ||
MRSA | ||||
 Oxacillin | 1 |  ≤ 17 | – |  ≥ 18 |
 Tetracycline | 30 |  ≤ 14 | 15–18 |  ≥ 19 |
 Linezolid | 30 | – | – |  ≥ 21 |
 Cefoxitin | 30 |  ≤ 24 | – |  ≥ 25 |
 Vancomycin | 30 | – | – |  ≥ 15 |
Enterococcus spp. | ||||
 Penicillin | 10 units |  ≤ 14 | – |  ≥ 15 |
 Ampicillin | 10 |  ≤ 16 | – |  ≥ 17 |
 Linezolid | 30 |  ≤ 20 | 21–22 |  ≥ 23 |
 Tetracycline | 30 |  ≤ 14 | 15–18 |  ≥ 19 |
 Vancomycin | 30 |  ≤ 14 | 15–16 |  ≥ 17 |
Other Enterobacteriaceae | ||||
 Cefazolin | 30 |  ≤ 14 | 15–17 |  ≥ 18 |
 Ceftazidime | 30 |  ≤ 14 | 15–17 |  ≥ 18 |
 Ampicillin | 10 |  ≤ 13 | 14–16 |  ≥ 17 |
 Gentamicin | 10 |  ≤ 12 | 13–14 |  ≥ 15 |
 Tetracycline | 30 |  ≤ 11 | 12–14 |  ≥ 15 |