Antibiotics

  • General
  • Above the diaphragm (Aspiration pneumonia, lung abscesses, oral infections)
    • 1) Clindamycin
  • Below the Diaphragm (Intra-abdominal anaerobic infections)
    • 1) Metronidazole
  • Monitoring
  • Aminoglycosides/Vancomycin
    • If IV ≥3 days or ≥2 days in a renal patient
  • Penicillin causing rash
    • Not a contraindication for cephalosporins
    • Breathing issues, edema are CIs
  • Amoxicillin/Clavulanic Acid (Augmentin)
  • Ampicillin/Sulbactam (Unasyn)
  • Ceftriaxone
  • SE: Cholestasis
  • Cefazolin
  • Prophylaxis for skin flora
  • Cefepime
  • Coverage
    • Pseudomonas, MSSA, Strep Pneumo, H. Influenzae
  • Misses
    • Enterococcus
  • SE: Neutropenia, thrombocytopenia, Seizure, Delirium, C. Difficile, Transaminitis, Hemolytic anemia, interstitial nephritis
  • Ceftaroline
  • 5th gen cephalosporin, only one that covers MRSA
  • Clindamycin
  • MOA: Inhibits protein synthesis
  • Effective against Bacteroides and c. perfringens
  • Chloramphenicol
  • 50S static
  • Associated w/ blood dyscrasias
  • Daptomycin (Cubicin)
  • Can be considered for MRSA infections when the isolate's vancomycin MIC is ≥2 nanograms/mL or when the vancomycin MIC is close to 2 nanograms/mL and the clinical response is poor
    • Test susceptibility first
  • Coverage
    • MRSA, VRE
  • SE: LFT elevations, Acute eosinophilic pneumonia, peripheral neuropathy, Falsely elevated INR, Rhabdomyolysis (CK (DC if ≥2000 or ≥1000 w/myopathy), stop statins)
  • Meropenem (Merrem)
  • Coverage
    • Pseudomonas
  • Metronidazole
  • MOA: Contains a nitro group that acts as an electron sink, capturing electrons and creating free radicals which disrupts DNA synthesis via a cytotoxic intermediate (Bactericidal)
  • Effective against Bacteroides, prevotella, fusobacterium, clostridium
  • SE:
    • Disulfiram-like reaction (severe flushing, tachycardia, palpitations, nausea, vomiting, hypotension) with alcohol
    • Metallic taste
    • Headache
  • Piperacillin-Tazobactam (Zosyn)
  • Coverage
    • Pseudomonas, Proteus
  • Misses
    • C. Difficile
  • SE: Rash, Drug fever, Prolonged PT, Leukopenia, Thrombocytopenia
  • Telavancin
  • Lipoglycopeptide derivative of vancomycin and can be given once daily
  • More side effects than Vancomycin, worse kidney injury
  • Tuberculosis Medications
  • Rifampin
    • Benign, red color to body secretions
  • Isoniazid
    • Peripheral Neuropathy
    • Use pyridoxine to prevent
  • Pyrazinamide
    • Benign, Hyperuricemia (Gout)
  • Ethambutol
    • Optic neuritis/color vision changes
    • Decrease dose in renal failure
  • TMP/SMX
  • CI: Warfarin/Methotrexate use, allergy, elderly with renal insufficiency
  • Vancomycin
  • Red Man Syndrome
    • MC adverse event, hypersensitivity not reaction
    • Usually 5-10 minutes after starting infusion
    • Diffuse erythema, pruritus, and tenderness over the skin above the waist
    • ± hypotension, dyspnea if severe
    • Treatment
    • Stop infusion, give antihistamines, restart infusion at slower rate
  • Dosing Guidelines

    • Area under the curve, Mean inhibitory concentration
    • Goal for AUC/MIC to be achieved in 24-48 hours
    • Empiric Therapy
    • AUC/MIC calculation for empiric therapy assumes MIC to be 1 nanogram/ml or less
    • MRSA Native Tricuspid Valve Endocarditis
    • AUC/MIC target of 400-600 mg*hour/L of Vancomycin to maximize efficacy and minimize nephrotoxicity
    • MRSA Prosthetic Valve Endocarditis
    • Vancomycin, Gentamicin, and Rifampin