Antimicrobials

Active against:

• Staphylococci spp. (including methicillin-resistant strains)
• Streptococci spp.
• Enterococci spp.
• Corynebacterium spp.
• Bacillus spp.
• Clostridium spp.
• Actinomyces spp.
• Propionibacterium spp.
• Listeria monocytogenes

Not active against:

• Vancomycin-resistant enterococci (VRE)
• Gram negative aerobic and anaerobic bacteria

Appropriate Uses:

• Serious infections due to β-lactam-resistant Gram-positive microorganisms, (e.g., MRSA infection)
• Infections due to gram-positive bacteria in patients with serious β-lactam allergy (defined as life-threatening allergic reactions)
• As part of empiric therapy for community acquired bacterial meningitis until culture and sensitivity are available
• First-line oral treatment of colitis due to Clostridium difficile
• As part of empiric therapy of presumed or confirmed bacterial infective endocarditis until culture and sensitivity are available
• Appropriate surgical prophylaxis in patients with life-threatening allergy to β-lactam antibiotics

Inappropriate Uses:

• Oral vancomycin is not absorbed and cannot be used to treat systemic infection
• Treatment (chosen for dosing convenience) of infections in patients with renal failure
• Treatment of infections due to β-lactam-resistant Gram-positive microorganisms that are not serious
• Treatment in response to a single blood culture positive for coagulase-negative staphylococci
• Continued empiric use for presumed infections in patients whose cultures are negative for β-lactam-resistant gram-positive organisms.
• Empiric antimicrobial therapy for a febrile neutropenic patient unless there is strong evidence at the outset that the infection is due to gram-positive microorganisms and the prevalence of infections due to MRSA in the hospital is substantial
• Surgical prophylaxis in a patient who does not have a life-threatening allergy to β-lactam antibiotics

• Excessive use is a risk factor for colonization and infection with vancomycin-resistant enterococci
• Pregnancy: Limited human data. Should be used only when benefit outweighs unknown risk to the fetus.
• Breastfeeding: Limited information; however, amounts in breast milk and oral bioavailability are low. Monitor nursing infant for GI symptoms.

• "Vancomycin infusion reaction": histamine-mediated erythema and pruritus over neck and upper torso, ± hypotension (associated with rapid drug administration) This is NOT an allergic reaction to vancomycin and does not preclude the use of vancomycin.
• Management of "Vancomycin infusion reaction":
  1. Extend the infusion duration to ≥ 2 hours
  2. Consider pre-treatment with hydroxyzine 50 mg PO 2 h prior to each dose; for NPO patients, diphenhydramine 25 - 50 mg may be given IV just prior to each dose.

• Ototoxicity: currently considered to be negligible

• Nephrotoxicity:
  • When trough is ≤ 15 mg, the incidence is < 10%
  • When trough is 15 - 20 mg/L, the incidence is 10 - 20%
  • Risk is increased when:
    • Duration of therapy exceeds 14 days
    • The dose ≥ 4 g/day
    • Trough levels are > 20 mg/L
    • Concomitant use of nephrotoxic agents (ie., aminoglycosides, amphotericin B, cisplatin, diuretics, NSAIDs, or radio-contrast dye)

• Neutropenia:
  • Vancomycin-induced neutropenia may occur with prolonged vancomycin exposure of > 7 days
  • If vancomycin induced neutropenia is suspected, discontinue vancomycin

• Thrombocytopenia:
  • Vancomycin-induced immune thrombocytopenia due to platelet reactive antibodies has been observed following a median of 7 days of vancomycin
  • Severe bleeding due to vancomycin-induced thrombocytopenia may occur
  • If vancomycin-induced thrombocytopenia is suspected, discontinue vancomycin
  • Platelet recovery is expected to occur within 7 – 14 days of discontinuing vancomycin

• Oral vancomycin is the treatment of choice for C. difficile colitis
• NOT indicated for any other infection
• Usual dosage is 125 mg orally QID for 10 – 14 days; data supporting the need for higher doses of vancomycin orally is lacking
• Oral vancomycin is administered as a solution, usually 125 mg/2.5 mL, prepared from the injectable product and either added to a beverage for the patient to drink or further diluted for administration via enteral feeding tube.

• Intermittent Infusion (IIV) Vancomycin
• Continuous Infusion (CIV) Vancomycin - Select Patients Only

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