Bugs and Drugs

Penicillin G / Pen VK / Ampicillin / Amoxicillin

GP: Strep, variable Enterococcus, Listeria (amp/amo); GN: Neisseria, E. coli, P. mirabilis, H. influenzae; Anaerobes: Clostridia, Peptostreptococcus, NOT B. fragilis; Other: T. pallidum, Nocardia; Elim: Renal; CNS: Good; Pearls: Penicillin/ampicillin empty stomach, amoxicillin ok with food.

Oxacillin / Nafcillin / Cloxacillin / Dicloxacillin

GP: MSSA, Strep; No MRSA, no Enterococcus; GN: none; Anaerobes: none; Elim: Oxacillin renal, Nafcillin hepatic; CNS: Good; Pearls: Dicloxacillin best PO, Nafcillin ↑ interstitial nephritis.

Ticarcillin / Piperacillin

GP: Same as PCN; GN: broad, Piperacillin covers Pseudomonas; Anaerobes: fair; Elim: Renal; CNS: Good; Pearls: High sodium load.

Amoxicillin/clavulanate

GP: Staph, Strep, Enterococcus; GN: AMP + β‑lactamase producers; Anaerobes: excellent incl. B. fragilis; Elim: Renal; CNS: Poor; Pearls: Clavulanate causes diarrhea.

Ampicillin/sulbactam

GP: Staph, Strep, Enterococcus; GN: AMP + β‑lactamase producers; Anaerobes: excellent; Elim: Renal; CNS: Good.

Piperacillin/tazobactam

GP: Staph (not MRSA), Enterococcus; GN: broad incl. Pseudomonas; Anaerobes: excellent; Elim: Renal; CNS: Good; Pearls: Timentin covers Stenotrophomonas.

Ticarcillin/clavulanate

GP: Poor staph; GN: β‑lactamase producers; Anaerobes: none; Other: Stenotrophomonas; Elim: Renal; CNS: Good.

Ceftazidime/avibactam

GP: poor staph; GN: ESBL, KPC; Anaerobes: none; Elim: Renal; CNS: Good.

Ceftolozane/tazobactam

GP: moderate; GN: MDR Pseudomonas; Anaerobes: moderate; Elim: Renal; CNS: Good.

Aztreonam

GP: none; GN: broad incl. Pseudomonas; Anaerobes: none; Elim: Renal; CNS: Good; Pearls: Safe in PCN allergy.

Imipenem/cilastatin

GP: Staph, Enterococcus; GN: excellent incl. Pseudomonas; Anaerobes: excellent; Elim: Renal; CNS: Good; Pearls: Highest seizure risk.

Meropenem

GP: Staph; GN: excellent incl. Pseudomonas; Anaerobes: excellent; Elim: Renal; CNS: Good; Pearls: Lower seizure risk.

Doripenem

GP: Staph; GN: excellent incl. Pseudomonas; Anaerobes: excellent; Elim: Renal; CNS: Good.

Ertapenem

GP: Staph; GN: broad but NOT Pseudomonas; Anaerobes: excellent; Elim: Renal; CNS: Good.

Cefazolin / Cephalexin / Cefadroxil (1st gen)

GP: Excellent MSSA, Strep; GN: moderate E. coli, Klebsiella, Proteus; Anaerobes: poor; Elim: Renal; CNS: Poor.

Cefuroxime / Cefaclor / Cefprozil (2nd gen)

GP: Good Staph, Strep; GN: +H. influenzae, M. catarrhalis; Anaerobes: poor; Elim: Renal; CNS: Fair; Pearls: Cefotetan has MTT side chain.

Cefoxitin / Cefotetan (2nd gen cephamycins)

GP: moderate; GN: similar to above; Anaerobes: some incl. B. fragilis; Elim: Renal; CNS: Poor.

Ceftriaxone / Cefotaxime / Cefdinir / Cefpodoxime (3rd gen)

GP: excellent Strep; GN: good; Anaerobes: poor; Elim: Ceftriaxone hepatic, others renal; CNS: Good; Pearls: Avoid ceftriaxone in neonates.

Ceftazidime (3rd gen)

GP: poor Staph; GN: excellent incl. Pseudomonas; Anaerobes: poor; Elim: Renal; CNS: Fair.

Cefepime (4th gen)

GP: moderate Staph; GN: excellent incl. Pseudomonas; Anaerobes: poor; Elim: Renal; CNS: Fair.

Ceftaroline (5th gen)

GP: MRSA, pneumococci; GN: community GN; Anaerobes: poor; Elim: Renal; CNS: Good.

Ceftobiprole (5th gen)

GP: MRSA, Enterococcus; GN: excellent incl. Pseudomonas; Anaerobes: poor; Elim: Renal; CNS: Good.

Cefiderocol

GP: poor; GN: excellent incl. MDR Pseudomonas; Anaerobes: poor; Elim: Renal; CNS: Good.

Ciprofloxacin

GP: poor Staph, poor Strep; GN: excellent incl. Pseudomonas; Anaerobes: poor; Other: atypicals; Elim: Renal; CNS: Good; Pearls: Avoid with antacids; photosensitivity.

Levofloxacin

GP: better Strep; GN: excellent; Anaerobes: poor; Other: atypicals; Elim: Renal; CNS: Good.

Moxifloxacin

GP: good Strep; GN: good; Anaerobes: moderate incl. B. fragilis; Other: atypicals; Elim: Hepatic; CNS: Good; Pearls: QT prolongation.

Gemifloxacin

GP: good Strep; GN: good; Anaerobes: poor; Other: atypicals; Elim: Hepatic; CNS: Good; Pearls: ↑ rash.

Amikacin / Gentamicin / Tobramycin

GP: synergy only (Staph, Strep, Enterococcus); GN: excellent incl. Pseudomonas; Anaerobes: none; Other: TB (strepto), MAI (amikacin); Elim: Renal; CNS: Poor; Pearls: Nephrotoxic, ototoxic.

Streptomycin

GP: synergy; GN: good; Anaerobes: none; Other: TB; Elim: Renal; CNS: Poor.

Erythromycin

GP: Staph (not MRSA), Strep; GN: variable; Anaerobes: some; Other: atypicals; Elim: Hepatic; CNS: Poor; Pearls: GI upset, QT prolongation.

Azithromycin

GP: Strep; GN: H. influenzae, M. catarrhalis; Anaerobes: none; Other: atypicals; Elim: Hepatic; CNS: Poor.

Clarithromycin

GP: Strep; GN: H. influenzae; Anaerobes: none; Other: atypicals, H. pylori; Elim: Hepatic; CNS: Poor.

Fidaxomicin

GP: C. diff only; GN: none; Anaerobes: none; Elim: GI; CNS: Poor.

Telithromycin

GP: macrolide‑resistant Strep; GN: similar to macrolides; Anaerobes: similar; Other: atypicals; Elim: Hepatic; CNS: Poor; Pearls: hepatotoxicity.

Tetracycline / Doxycycline / Minocycline

GP: Staph (some MRSA), Strep; GN: Neisseria, H. influenzae; Anaerobes: moderate; Other: atypicals, Lyme, Rickettsia; Elim: Mixed; CNS: Poor; Pearls: Photosensitivity, avoid in pregnancy/children.

Tigecycline

GP: MRSA, VRE; GN: broad but NOT Pseudomonas; Anaerobes: excellent; Other: atypicals; Elim: Hepatic; CNS: Poor; Pearls: N/V.

TMP/SMX

GP: MRSA, Staph, variable Strep; GN: broad incl. Stenotrophomonas; Anaerobes: none; Other: PCP, Nocardia; Elim: Renal; CNS: Good; Pearls: Photosensitivity, hyperK.

EES/sulfisoxazole

GP: similar to erythromycin; GN: H. influenzae; Anaerobes: none; Other: atypicals; Elim: Renal; CNS: Poor.

Vancomycin

GP: MRSA, Enterococcus (not VRE); GN: none; Anaerobes: C. diff (oral); Elim: Renal; CNS: Poor; Pearls: Red man syndrome.

Dalbavancin

GP: MRSA; GN: none; Anaerobes: none; Elim: Renal/other; CNS: Poor; Pearls: weekly dosing.

Oritavancin

GP: MRSA, VRE; GN: none; Anaerobes: none; Elim: Renal; CNS: Poor.

Quinupristin/dalfopristin

GP: MRSA, VRE (faecium); GN: poor; Anaerobes: good; Other: atypicals; Elim: Hepatic; CNS: Poor; Pearls: arthralgias, myalgias.

Linezolid

GP: MRSA, VRE; GN: none; Anaerobes: same as PCN; Other: mycobacteria; Elim: Mixed; CNS: Fair; Pearls: serotonin syndrome, myelosuppression.

Tedizolid

GP: MRSA, VRE; GN: none; Anaerobes: same as PCN; Elim: Hepatic; CNS: Fair.

Daptomycin

GP: MRSA, VRE; GN: none; Anaerobes: none; Elim: Renal; CNS: Poor; Pearls: Not for pneumonia (inactivated by surfactant).

Telavancin

GP: MRSA; GN: none; Anaerobes: none; Elim: Renal; CNS: Poor; Pearls: QT prolongation.

Rifampin

GP: good but never alone; GN: H. influenzae, N. meningitidis; Anaerobes: none; Other: TB; Elim: Hepatic; CNS: Fair; Pearls: CYP inducer, orange secretions.

Clindamycin

GP: Strep, Staph (some MRSA); GN: none; Anaerobes: excellent incl. B. fragilis; Elim: Hepatic; CNS: Poor; Pearls: diarrhea, C. diff risk.

Metronidazole

GP: none; GN: H. pylori; Anaerobes: excellent incl. B. fragilis, C. diff; Other: protozoa; Elim: Hepatic; CNS: Good; Pearls: disulfiram reaction.

Chloramphenicol

GP: excellent Strep; GN: good; Anaerobes: excellent; Other: Rickettsia; Elim: Hepatic; CNS: Good; Pearls: aplastic anemia.

Nitrofurantoin

GP: Staph, Enterococcus; GN: E. coli, Klebsiella; Anaerobes: none; Elim: Renal; CNS: none; Pearls: only for cystitis, avoid if CrCl <50.

Fosfomycin

GP: Enterococcus; GN: E. coli; Anaerobes: none; Elim: Renal; CNS: none; Pearls: single‑dose cystitis therapy.

Amphotericin B

GP: Candida, Cryptococcus; Moulds: Histoplasma, Aspergillus; CNS: Poor; Pearls: nephrotoxicity, infusion reactions.

Flucytosine (5‑FC)

Yeasts: Candida, Cryptococcus; Moulds: Aspergillus; Elim: Renal; CNS: Good; Pearls: use only in combination.

Ketoconazole

Yeasts: Candida; Moulds: Histoplasma; Elim: Hepatic; CNS: Poor; Pearls: needs acidic pH.

Fluconazole

Yeasts: Candida (not krusei), Cryptococcus; Moulds: Coccidioides; Elim: Renal; CNS: Good; Pearls: excellent PO bioavailability.

Itraconazole

Yeasts: Candida; Moulds: Aspergillus, Histoplasma, Blastomyces; Elim: Hepatic; CNS: Poor; Pearls: capsule needs acid, solution does not.

Voriconazole

Yeasts: Candida; Moulds: Aspergillus; Elim: Hepatic; CNS: Good; Pearls: visual disturbances.

Posaconazole

Yeasts: Candida; Moulds: zygomycetes, fusarium; Elim: Hepatic; CNS: Poor; Pearls: take with high‑fat food.

Isavuconazole

Yeasts: Candida; Moulds: similar to posaconazole; Elim: Hepatic; CNS: Poor; Pearls: QT shortening.

Caspofungin

Yeasts: Candida (not Crypto); Moulds: Aspergillus; Elim: Hydrolysis; CNS: Poor; Pearls: monitor LFTs.

Micafungin

Yeasts: Candida; Moulds: Aspergillus; Elim: Hepatic; CNS: Poor; Pearls: histamine reactions.

Anidulafungin

Yeasts: Candida; Moulds: Aspergillus; Elim: slow degradation; CNS: Poor; Pearls: no CYP interactions.

Terbinafine

Yeasts: not C. albicans; Moulds: dermatophytes; Elim: Hepatic; CNS: Poor; Pearls: nail infections.

Griseofulvin

Moulds: dermatophytes; Elim: Hepatic; CNS: Poor; Pearls: photosensitivity, take with fatty food.