Vancomycin, Random, Serum
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Vancomycin is an antibiotic used to treat infections caused by gram-
positive organisms that are resistant to beta-lactam antibiotics, such
as methicillin-resistant staphylococci (MRSA), Staphylococcus
viridans group, penicillin/cephalosporin-resistant Streptococcus
pneumoniae, and penicillin/ampicillin-resistant Enterococcus
species. The oral formulation, which is not absorbed, is used in the
treatment of pseudomembranous colitis caused by Clostridium difficile.
Vancomycin is also used when patients are intolerant or allergic to beta
Vancomycin has been associated with nephrotoxicity and ototoxicity,
although it appears that many of these reports reflected impurities in
early formulations. Monitoring of vancomycin-related nephrotoxicity
is recommended only for patients with reduced renal function, those
receiving aggressive or prolonged vancomycin regimens, or those at
high risk including patients comedicated with other nephrotoxic agents.
Trough concentrations are recommended for therapeutic monitoring of
vancomycin, preferably acquired at steady state (just before fourth
dose). To avoid development of resistance, vancomycin trough levels
should remain >10 mcg/mL. Complicated infections require higher target
levels, typically 15 to 20 mcg/mL. Peak concentrations do not correlate
well to efficacy or nephrotoxicity, but may be useful for
pharmacokinetic studies or for select patients.
Monitoring adequacy of drug concentration during vancomycin
This unit code is used whenever a specimen is submitted
or collected without collection timing information. Random levels
may be ordered when attempting to determine when to dose
vancomycin in patients with renal impairment or those undergoing
Trough levels correlate better with efficacy than peak levels, with
target trough levels of 10 mcg/mL to 20 mcg/mL, depending on the
type of infection.
Peak levels are not recommended for monitoring, except in
select circumstances such as when performing pharmacokinetic
analyses (eg, area under the curve [AUC] determinations).
Typical peak levels are between 25 to 50 mcg/mL.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Therapeutic concentration: 10.0-20.0 mcg/mL
Complicated infections: 15.0-20.0 mcg/mL
Therapeutic concentration: 25.0-50.0 mcg/mL
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Rybak M, Lomaestro B, Rotschafer JC, et al: Therapeutic drug
monitoring of vancomycin in adult patients: A consensus review
of the American Society of Health-System Pharmacists, the
Infectious Diseases Society of America, and the Society of
Infectious Diseases Pharmacists. Am J Health Syst Pharm
2. Estes L, Wilson J: Mayo Guide to Antimicrobial Therapy,
Mayo Clinic, 2005-2008