Tool
Antimicrobial Spectrum
A quick-reference chart of expected antimicrobial susceptibility patterns for commonly encountered organisms. Search by organism or filter by Gram stain category.
| Organism | Ampicillin | Amoxicillin-clavulanate | Piperacillin-tazobactam | Ceftriaxone | Cefepime | Meropenem | Aztreonam | Ciprofloxacin | Levofloxacin | TMP-SMX | Doxycycline | Vancomycin | Linezolid | Daptomycin | Metronidazole |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Staphylococcus aureus (MSSA) | R | S | S | S | S | S | R | S | S | S | S | S | S | S | R |
| Staphylococcus aureus (MRSA) | R | R | R | R | R | R | R | I | I | S | S | S | S | S | R |
| Streptococcus pneumoniae | S | S | S | S | S | S | R | R | S | I | I | S | S | S | R |
| Streptococcus pyogenes (GAS) | S | S | S | S | S | S | R | R | I | R | I | S | S | S | R |
| Streptococcus agalactiae (GBS) | S | S | S | S | S | S | R | R | I | R | I | S | S | S | R |
| Enterococcus faecalis | S | S | S | R | R | R | R | I | I | R | I | S | S | S | R |
| Enterococcus faecium | R | R | R | R | R | R | R | R | R | R | I | I | S | S | R |
| Escherichia coli | I | S | S | S | S | S | S | I | I | I | I | R | R | R | R |
| Klebsiella pneumoniae | R | S | S | S | S | S | S | S | S | S | I | R | R | R | R |
| Proteus mirabilis | S | S | S | S | S | S | S | S | S | S | R | R | R | R | R |
| Pseudomonas aeruginosa | R | R | S | R | S | S | S | S | S | R | R | R | R | R | R |
| Acinetobacter baumannii | R | R | I | R | I | I | R | I | I | I | I | R | R | R | R |
| Stenotrophomonas maltophilia | R | R | R | R | R | R | R | I | S | S | S | R | R | R | R |
| Serratia marcescens | R | R | S | S | S | S | S | S | S | S | I | R | R | R | R |
| Enterobacter cloacae | R | R | I | I | S | S | I | S | S | S | I | R | R | R | R |
| Citrobacter freundii | R | R | I | I | S | S | I | S | S | S | I | R | R | R | R |
| Haemophilus influenzae | I | S | S | S | S | S | S | S | S | I | I | R | R | R | R |
| Neisseria meningitidis | S | S | S | S | S | S | S | S | S | I | I | R | R | R | R |
| Bacteroides fragilis | R | S | S | R | R | S | R | R | R | R | R | R | I | R | S |
| Clostridioides difficile | R | R | R | R | R | R | R | R | R | R | R | S | — | — | S |
| Mycoplasma pneumoniae | R | R | R | R | R | R | R | S | S | R | S | R | R | R | R |
| Legionella pneumophila | R | R | R | R | R | R | R | S | S | R | S | R | R | R | R |
| Chlamydophila pneumoniae | R | R | R | R | R | R | R | S | S | R | S | R | R | R | R |
23 of 23 organisms shown